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TI-2026-53918 Aliases CVE-2026-77219GHSA-q8pr-2495-3jw7

GNU Emacs < 31.0.91 Heap Over-Read via PBM/PPM/PGM Image Loader

Priority LOW 29CWE-125Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
High · None · High
Fix status
Partial Red Hat: 5 fixed, 2 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.

Summary

GNU Emacs before 31.0.91 contains an integer overflow in the PBM/PPM/PGM image loader that allows an attacker to leak heap memory contents by supplying a crafted image with large dimensions and an elevated max color index. The image loader multiplies image dimensions and channel count using signed integer arithmetic; for sufficiently large values, the result wraps to a negative number, bypassing the bounds check and causing the pixel reader to access heap memory past the end of the allocated buffer. The over-read contents are interpreted as pixel color values and rendered on screen.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00128 2nd percentileScored 2026-11-07
Fix Partial Emacs (GNU): 31.0.91Red Hat: 3 advisoriesRed Hat: 5 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
GNUEmacsbefore 31.0.9131.0.91Patch availableCNA
  • Emacs VendorGNU Affected before 31.0.91 Fixed in 31.0.91 Patch available CNA

Remediation

  • Fix · CNA Emacs (GNU) Fixed in 31.0.91

Red Hat 3 advisories

  • RHSA-2026:84591 Released 2026-10-19 · Red Hat rating Important
    emacs security update
    • Red Hat Enterprise Linux AppStream (v. 10) emacs-1:29.4-14.el10_2.3, emacs-common-1:29.4-14.el10_2.3, emacs-lucid-1:29.4-14.el10_2.3 +1
    • Red Hat Enterprise Linux BaseOS (v. 10) emacs-1:29.4-14.el10_2.3, emacs-filesystem-1:29.4-14.el10_2.3
  • RHSA-2026:80507 Released 2026-10-12 · Red Hat rating Important
    emacs security update
    • Red Hat Enterprise Linux AppStream (v. 9) emacs-1:27.2-18.el9_8.2, emacs-common-1:27.2-18.el9_8.2, emacs-filesystem-1:27.2-18.el9_8.2 +2
  • RHSA-2026:80506 Released 2026-10-12 · Red Hat rating Important
    emacs security update
    • Red Hat Enterprise Linux AppStream (v. 8) emacs-1:26.1-15.el8_10.2, emacs-common-1:26.1-15.el8_10.2, emacs-lucid-1:26.1-15.el8_10.2 +2
    • Red Hat Enterprise Linux BaseOS (v. 8) emacs-1:26.1-15.el8_10.2, emacs-filesystem-1:26.1-15.el8_10.2

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:84591
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:80506
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:80507
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:84591
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:80506

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-77219
  2. 2026-10-03 Alias added: GHSA-q8pr-2495-3jw7
  3. 2026-10-12 Fix available: RHSA-2026:80507 · Red Hat
  4. 2026-10-12 Fix available: Red Hat Enterprise Linux AppStream (v. 9) · Red Hat
  5. 2026-10-12 Fix available: RHSA-2026:80506 · Red Hat
  6. 2026-10-12 Fix available: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux BaseOS (v. 8) · Red Hat
  7. 2026-10-19 Fix available: RHSA-2026:84591 · Red Hat
  8. 2026-10-19 Fix available: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10) · Red Hat

References

Patch 1

Other 2

  • TI-2026-19388 telnetd in GNU Inetutils through 2.7 allows remote authentication bypass via a "-f root"… KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-05975 GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed… KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-05157 GNU Bash through 4.3 processes trailing strings after function definitions in the values… KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-05164 GNU Bash through 4.3 bash43-026 does not properly parse function definitions in the… KEVCVSS 3.1HIGH 8.8
  • TI-2023-04522 Glibc: buffer overflow in ld.so leading to privilege escalation KEVCVSS 3.1HIGH 7.8
  • TI-2009-03392 The TLS protocol, and the SSL protocol 3.0 and possibly earlier, as used in Microsoft… CVSS 3.1CRITICAL 9.8
See all 1272 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences