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Security Bulletin: IBM Instana Observability is affected by multiple vulnerabilities within Instana Agent container image

Security Bulletin


Summary

Multiple vulnerabilities were addressed in IBM Observability with Instana within Instana Agent container image build 1.0.324

Vulnerability Details

CVEID:   CVE-2026-44892
DESCRIPTION:   Netty is a network application framework for development of protocol servers and clients. Prior to version 4.2.15.Final, the default configuration of the `Http3ConnectionHandler` in the Netty HTTP/3 codec lacks an enforced maximum header size limit. When a peer does not explicitly specify `HTTP3_SETTINGS_MAX_FIELD_SECTION_SIZE`, the implementation defaults to an unbounded limit. This insecure default configuration allows a malicious client or server to send an enormous number of headers, leading to a memory exhaustion Denial of Service via an `OutOfMemoryError`. Version 4.2.15.Final contains a patch.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   security-advisories@github.com
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-44249
DESCRIPTION:   Netty is a network application framework for development of protocol servers and clients. In netty-handler prior to versions 4.1.135.Final and 4.2.15.Final, an attacker can bypass IPv6 subnet rules due to an incorrect masking operation in IpSubnetFilterRule.compareTo(). Valid public IP addresses can bypass the restrictions. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
CWE:   CWE-284: Improper Access Control
CVSS Source:   security-advisories@github.com
CVSS Base score:   8.1
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H)

CVEID:   CVE-2026-11352
DESCRIPTION:   An issue in curl’s QUIC UDP receive function allows a malicious HTTP/3 server to trigger a remote denial of service against a curl or libcurl client. Because the helper function discards zero-length UDP datagrams before counting them toward the per-call packet budget, a connected QUIC peer can continuously stream empty datagrams to indefinitely stall the client.
CWE:   CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')
CVSS Source:   CISA ADP
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-8286
DESCRIPTION:   A vulnerability exists where a new transfer that uses STARTTLS to upgrade the connection might reuse an existing live connection even though the TLS configuration mismatches so it should not.
CWE:   CWE-295: Improper Certificate Validation
CVSS Source:   CISA ADP
CVSS Base score:   8.1
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N)

CVEID:   CVE-2026-8925
DESCRIPTION:   The curl logic that works with SASL authentication could end up cleaning up the GSASL context *twice* without clearing the pointer in between, making it `free()` the same pointer twice.
CWE:   CWE-415: Double Free
CVSS Source:   CISA ADP
CVSS Base score:   9.8
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

CVEID:   CVE-2026-9547
DESCRIPTION:   When a libcurl-based application performs transfers via `SCP://` or `SFTP://` and utilizes the `CURLOPT_SSH_KEYFUNCTION` callback, it may silently accept an untrusted server. This vulnerability occurs when a server presents a host key type that does not match the specific key type already recorded for that host in the `known_hosts` file. Instead of rejecting the mismatch, the callback mechanism fails to properly enforce the restriction, allowing the connection to succeed without warning and risking a potential man-in-the-middle attack.
CVSS Source:   CISA ADP
CVSS Base score:   7.4
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N)

CVEID:   CVE-2026-45416
DESCRIPTION:   Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, SslClientHelloHandler.decode() reads the 24-bit TLS handshake length and, when the ClientHello does not fit in the first record, eagerly allocates `ctx.alloc().buffer(handshakeLength)` (line 161). The guard at line 140 is `handshakeLength maxClientHelloLength && maxClientHelloLength != 0`, and the commonly-used SniHandler/AbstractSniHandler constructors (SniHandler(Mapping), SniHandler(AsyncMapping), AbstractSniHandler()) pass maxClientHelloLength=0 and handshakeTimeoutMillis=0, so the length guard is disabled and no timeout is scheduled. A 16 MiB request exceeds the default pooled chunk size and becomes a huge/unpooled allocation performed immediately. The buffer is retained in the handler until the channel closes. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
CWE:   CWE-770: Allocation of Resources Without Limits or Throttling
CVSS Source:   security-advisories@github.com
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-11586
DESCRIPTION:   By default, curl automatically responds to WebSocket PING frames. Because curl lacks an upper bound on memory allocation for unacknowledged frames, a malicious server can exhaust all available memory by flooding curl with rapid, sequential PING messages.
CWE:   CWE-770: Allocation of Resources Without Limits or Throttling
CVSS Source:   CISA ADP
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-12064
DESCRIPTION:   When a user invokes curl using a schemeless URL combined with `--proto-default` sftp (or scp), a disconnect occurs between the tool layer and libcurl. The tool layer incorrectly infers the URL scheme, which erroneously bypasses the initialization of critical SSH security options like CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256 and CURLOPT_SSH_KNOWNHOSTS. Conversely, the libcurl runtime successfully honors CURLOPT_DEFAULT_PROTOCOL and establishes the connection via SFTP/SCP as specified. Because the tool layer skipped the security configuration, these SSH host verification options are silently omitted, causing curl to connect to an unverified SSH remote host without throwing an error.
CWE:   CWE-295: Improper Certificate Validation
CVSS Source:   CISA ADP
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N)

CVEID:   CVE-2026-41838
DESCRIPTION:   IDs for WebSocket sessions in the spring-websocket module are not cryptographically unpredictable, which may be possible to exploit in combination with inadequate authorization rules. Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.
CWE:   CWE-330: Use of Insufficiently Random Values
CVSS Source:   NVD
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)

CVEID:   CVE-2026-41848
DESCRIPTION:   Applications may be vulnerable to a Regular Expression Denial of Service (ReDoS) attack if an attacker is able to provide a pattern which is then directly or indirectly supplied to one of the following methods in AntPathMatcher: match(String pattern, String path), matchStart(String pattern, String path), extractUriTemplateVariables(String pattern, String path). Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.
CWE:   CWE-1333: Inefficient Regular Expression Complexity
CVSS Source:   NVD
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-41851
DESCRIPTION:   Applications which accept user-supplied Spring Expression Language (SpEL) expressions may be vulnerable to a Denial of Service (DoS) attack if the evaluation of a SpEL expression triggers unbounded cache growth. Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.
CWE:   CWE-770: Allocation of Resources Without Limits or Throttling
CVSS Source:   NVD
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-19283
DESCRIPTION:   IBM Instana Agent Operator could allow an authenticated remote attacker to obtain sensitive information, caused by missing destination namespace validation when copying etcd mTLS client credentials from the openshift-etcd system namespace into an attacker-controlled namespace.
CWE:   CWE-863: Incorrect Authorization
CVSS Source:   IBM
CVSS Base score:   7.7
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N)

CVEID:   CVE-2026-47244
DESCRIPTION:   Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, DefaultHttp2Connection.DefaultEndpoint initialises maxActiveStreams/maxStreams to Integer.MAX_VALUE, and Http2Settings never inserts SETTINGS_MAX_CONCURRENT_STREAMS by default (Http2Settings.java:305-307 only clamps a user-supplied value). Unless the application explicitly calls initialSettings().maxConcurrentStreams(n), a Netty HTTP/2 server advertises no limit and enforces none locally. Each open stream allocates a DefaultStream object, PropertyMap slots, flow-controller state and IntObjectHashMap entry; with ~2^30 permissible odd stream IDs a single TCP connection can create hundreds of thousands of long-lived stream objects. This is also the precondition for CVE-2023-44487-style Rapid-Reset amplification, where the absence of a low concurrent cap multiplies backend work. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   security-advisories@github.com
CVSS Base score:   5.3
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)

CVEID:   CVE-2026-48043
DESCRIPTION:   Netty is a network application framework for development of protocol servers and clients. In netty-codec-http2 prior to versions 4.1.135.Final and 4.2.15.Final, the `DelegatingDecompressorFrameListener` class orchestrates HTTP/2 decompression by embedding a per-stream `EmbeddedChannel` that runs the appropriate decompression codec (gzip, deflate, zstd) and forwards decompressed chunks to a wrapped listener. Each decompressed chunk is a pooled `ByteBuf` handed to an anonymous `ChannelInboundHandlerAdapter` tail handler, which becomes the sole owner responsible for releasing it. A remote peer could send frames that would result in the flow-controller throwing and so trigger a resource leak which at the end might take down the whole JVM due OOME. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   NVD
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-19274
DESCRIPTION:   IBM Instana Agent Operator could allow an authenticated Kubernetes tenant to hijack or permanently destroy another tenant's cluster-level RBAC permissions, caused by cluster-scoped RBAC objects being keyed solely by the bare CR name with no namespace disambiguation, allowing a same-named `InstanaAgent` CR in an attacker-controlled namespace to silently overwrite the shared `ClusterRoleBinding` or delete it outright and revoke the victim agent's cluster monitoring access.
CWE:   CWE-284: Improper Access Control
CVSS Source:   IBM
CVSS Base score:   9.6
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H)

CVEID:   CVE-2026-44894
DESCRIPTION:   Netty is a network application framework for development of protocol servers and clients. NoQuicTokenHandler is the tokenHandler used when the application does not set one. Prior to version 4.2.15.Final, its writeToken() returns false (server will not send Retry — acceptable), but validateToken() unconditionally `return 0`. In QuicheQuicServerCodec.handlePacket(), a non-negative return from validateToken() is interpreted as 'token is valid, ODCID starts at offset 0', causing the server to call quiche_accept as if the client's address had been validated by a Retry round-trip. Per RFC 9000 §8.1, a validated address lifts the 3× anti-amplification send limit. Thus any attacker who includes ANY non-empty token bytes in an Initial packet — with a spoofed victim source IP — causes the Netty server to treat the victim as validated and reflect full-size handshake flights (certificates, etc.) toward it without the 3× cap. The correct 'no token handler' semantics would be to return -1 (invalid) so the normal un-validated path and amplification limit apply. Version 4.2.15.Final patches the issue.
CWE:   CWE-940: Improper Verification of Source of a Communication Channel
CVSS Source:   security-advisories@github.com
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N)

CVEID:   CVE-2026-15308
DESCRIPTION:   The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   NVD
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-41841
DESCRIPTION:   Spring MVC and WebFlux applications are vulnerable to Information Disclosure attacks when resolving static resources. Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.
CWE:   CWE-524: Use of Cache Containing Sensitive Information
CVSS Source:   security@vmware.com
CVSS Base score:   5.9
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N)

CVEID:   CVE-2026-41842
DESCRIPTION:   Spring MVC and WebFlux applications are vulnerable to Denial of Service (DoS) attacks when resolving static resources. Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   security@vmware.com
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-41843
DESCRIPTION:   Spring MVC and WebFlux applications are vulnerable to Path Traversal attacks when resolving static resources. Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.
CWE:   CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CVSS Source:   security@vmware.com
CVSS Base score:   5.9
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N)

CVEID:   CVE-2026-41844
DESCRIPTION:   A Spring MVC or Spring WebFlux application which configures a mapping for "/**" where the view name is not explicitly specified allows an attacker to craft a link resulting in a 302 redirect to an arbitrary external host via the redirect: prefix. Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.
CWE:   CWE-601: URL Redirection to Untrusted Site ('Open Redirect')
CVSS Source:   NVD
CVSS Base score:   6.1
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N)

ID:   GHSA-2r2c-cx56-8933
DESCRIPTION:   A high-severity vulnerability exists in the JLine3 remote-telnet module where the Telnet server fails to enforce an upper bound on terminal dimensions received via the NAWS option. By sending repeated requests with extremely large terminal sizes, an unauthenticated remote attacker can trigger continuous rendering operations, leading to CPU exhaustion and denial of service.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   GitHub
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

ID:   GHSA-47qp-hqvx-6r3f
DESCRIPTION:   The JLine3 Telnet server (remote-telnet module) does not limit the number of environment variables a client may inject via the Telnet NEW-ENVIRON option. An
unauthenticated attacker can flood the server with a large number of unique variable pairs before sending the terminating IAC SE byte, exhausting JVM heap memory and causing an OutOfMemoryError (denial of service). Approximately 3–4 MB of network traffic is sufficient to consume a 512 MB JVM heap.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   GitHub
CVSS Base score:   6.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)The JLine3 Telnet server (remote-telnet module) does not limit the number of environment variables a client may inject via the Telnet NEW-ENVIRON option. An unauthenticated attacker can flood the server with a)

Affected Products and Versions

Affected Product(s)Version(s)
IBM Observability with Instana (Agent)Build 1.0.303 to 1.0.323

Remediation/Fixes

IBM strongly recommends addressing these vulnerabilities now by updating IBM Observability with Instana to the latest release as described here:

https://www.ibm.com/docs/en/instana-observability/saas?topic=agents-updating-host 

Affected Product(s)Version(s)Remediation/Fixes/Instructions
IBM Observability with Instana (Agent)Build 1.0.303 to 1.0.323Build 1.0.324

Workarounds and Mitigations

None

Get Notified about Future Security Bulletins

References

Off

Acknowledgement

Change History

02 Sep 2026: Initial Publication

*The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin.

Disclaimer

According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES ""AS IS"" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY. In addition to other efforts to address potential vulnerabilities, IBM periodically updates the record of components contained in our product offerings. As part of that effort, if IBM identifies previously unidentified packages in a product/service inventory, we address relevant vulnerabilities regardless of CVE date. Inclusion of an older CVEID does not demonstrate that the referenced product has been used by IBM since that date, nor that IBM was aware of a vulnerability as of that date. We are making clients aware of relevant vulnerabilities as we become aware of them. "Affected Products and Versions" referenced in IBM Security Bulletins are intended to be only products and versions that are supported by IBM and have not passed their end-of-support or warranty date. Thus, failure to reference unsupported or extended-support products and versions in this Security Bulletin does not constitute a determination by IBM that they are unaffected by the vulnerability. Reference to one or more unsupported versions in this Security Bulletin shall not create an obligation for IBM to provide fixes for any unsupported or extended-support products or versions.

Document Location

Worldwide

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Document Information

Modified date:
02 September 2026

Initial Publish date:
02 September 2026

UID

ibm17286070