CVE-2026-91186

Source
https://cve.org/CVERecord?id=CVE-2026-91186
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-91186.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-91186
Aliases
  • GHSA-gx8f-4rpc-4fjw
Published
2026-10-20T14:47:52Z
Modified
2026-10-21T03:00:11Z
Severity
  • 8.4 (High) CVSS_V4 - CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
PNG decoder: a duplicate IHDR chunk after IDAT resizes the image after allocation, causing a heap out-of-bounds write
Details

The PNG chunk reader has no notion of chunk ordering. It records whether an IDAT has been seen and whether a tRNS has already supplied transparency, but nothing prevents an IHDR being read a second time.

A PNG carries exactly one IHDR and it is the first chunk. A file that places a second one after IDAT rewrites the image width, height, bit depth and pixel depth after the decoded-data buffer has already been allocated and filled from the original values. The pass that reverses the PNG row filters then derives its own extent from the new dimensions and walks the old allocation, moving image bytes past the end of it.

The buffer is allocated by GUIX rather than supplied by the caller, so the application has no way to size it defensively. The decoder is compiled in by default.

Database specific
{
    "cna_assigner":  "eclipse",
    "cwe_ids":  [
        "CWE-125",
        "CWE-787"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/91xxx/CVE-2026-91186.json"
}
References

Affected packages

Git / github.com/eclipse-threadx/guix

Affected ranges

Type
GIT
Repo
https://github.com/eclipse-threadx/guix
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Last Affected
Database specific
Show details
{
    "extracted_events":  [
        {
            "range":  [
                {
                    "introduced":  "0"
                },
                {
                    "last_affected":  "6.5.1.202602a"
                }
            ],
            "source":  "AFFECTED_FIELD",
            "strategy":  "StandardRange"
        }
    ]
}

Affected versions

v6.*
v6.0.1_rel
v6.0.2_rel
v6.0_rel
v6.1.10_rel
v6.1.11_rel
v6.1.12_rel
v6.1.3_rel
v6.1.4_rel
v6.1.5_rel
v6.1.6_rel
v6.1.7_rel
v6.1.8_rel
v6.1.9_rel
v6.1_rel
v6.2.0_rel
v6.2.1_rel
v6.3.0_rel
v6.4.0_rel
v6.4.1_rel
v6.4.2_rel
v6.4.3.202503_rel
v6.4.5.202504_rel
v6.5.1.202602_rel
v6.5.1.202602a_rel

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-91186.json"