Security Bulletin: Multiple vulnerabilities in rpm.rte affect AIX.

Vulnerability Details

CVEID:   CVE-2026-41992
DESCRIPTION:   GNU gzip contains a global buffer overflow vulnerability in the LZH decompression logic caused by improper reuse of shared global state between different decompression formats within a single execution. GNU gzip maintains a global array that is shared across the LZ77, LZW, and LZH decompression routines and is not reinitialized between files processed in the same invocation. By decompressing a specially crafted LZW file followed by a specially crafted LZH file in a single gzip -d command, an attacker can poison the shared global state and subsequently trigger an out‑of‑bounds read in the LZH decoder. The LZH decompression logic follows stale values left in the shared array, causing reads past the end of the allocated global buffer. This issue has been fixed in commits 63dbf6b3b9e6e781df1a6a64e609b10e23969681 and e7378c2d421be6a286922374425680bbe9ad8b7d.
CWE:   CWE-126: Buffer Over-read
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-2026-56288
DESCRIPTION:   GNU patch is vulnerable to a NULL pointer dereference when processing a specially crafted unified-diff patch file. Improper handling of consecutive end-of-file newline markers can corrupt internal hunk (single block of changes in diff) data structures, causing the application to pass a NULL pointer to fwrite() during patch processing. An attacker can trigger this condition with a malicious patch file, causing the utility to crash and resulting in a denial of service. This issue has been fixed in the commit e6d6a4e021660679d7fc9150f981d4920f722313
CWE:   CWE-476: NULL Pointer Dereference
CVSS Source:   NVD
CVSS Base score:   5.5
CVSS Vector:   (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-56289
DESCRIPTION:   GNU patch is vulnerable to a denial of service (DoS) due to improper validation of hunk (single block of changes in diff) line offsets in unified-diff input. A specially crafted patch can specify an extremely large line number, causing the application to enter an effectively infinite processing loop while attempting to locate the requested position. This results in excessive CPU consumption and prevents the process from completing. An attacker can trigger this behavior by supplying a malicious patch file, causing the utility to become unresponsive and require manual termination. This issue has been fixed in the commit faba04ef4f2b410257f76c1b9dc85e350929c4b9
CWE:   CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')
CVSS Source:   NVD
CVSS Base score:   5.5
CVSS Vector:   (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-18743
DESCRIPTION:   A flaw was found in popt. This vulnerability allows an attacker to provide specially crafted configuration content to a host, which, when loaded, can lead to a small memory corruption issue. This occurs because of an error in how the `poptConfigFileToString` function reallocates memory for buffers. Successful exploitation could result in heap metadata corruption, potentially causing the affected process to become unavailable (denial of service).
CWE:   CWE-131: Incorrect Calculation of Buffer Size
CVSS Source:   secalert@redhat.com
CVSS Base score:   2.5
CVSS Vector:   (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L)

CVEID:   CVE-2026-18739
DESCRIPTION:   A flaw was found in popt, a command-line option parsing library. An off-by-one error in the poptStuffArgs function, when repeatedly called by a host application or through deep alias nesting, can lead to corruption of internal program data. This corruption could potentially enable a local attacker to execute arbitrary code if the host application then unsafely processes the altered data.
CWE:   CWE-787: Out-of-bounds Write
CVSS Source:   secalert@redhat.com
CVSS Base score:   2.5
CVSS Vector:   (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L)

CVEID:   CVE-2026-18839
DESCRIPTION:   An integer underflow was found in the popt library when formatting help text for option tables that exceed the terminal width. A local user who can cause an application to print help under those conditions may cause that application to crash or fail to display help, resulting in a denial of service of the affected application.
CWE:   CWE-191: Integer Underflow (Wrap or Wraparound)
CVSS Source:   secalert@redhat.com
CVSS Base score:   2.2
CVSS Vector:   (CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L)