Medium [CVE-2026-71394] use of uninitialized memory via a malicious font file
This medium-severity Red Hat Linux advisory covers CVE-2026-71394.
Android app · Google Play
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
GNU Emacs for Android improperly validates the table header input in sfnt_read_table_directory() in src/sfnt.c.
Due to an incorrect comparison variable in the read-length check, a crafted font file that claims to contain more table directory entries than actually present causes the parser to return a struct with uninitialized heap memory in the table directory entries.
An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This leads to the use of uninitialized heap data in subsequent table lookups, potentially resulting in information disclosure, crashes, or arbitrary memory access on 32-bit targets.
This issue is fixed after commit 7621ee1d01229d50e5c0cddea6bf0b01095a62cf Improper validation of table header input in the `sfnt_read_table_directory()` function allows a crafted font file to cause the parser to return a structure with uninitialized heap memory.
An attacker can deliver a malicious font file, leading to the use of this uninitialized data in subsequent table lookups. Red Hat severity: Important — CVSS 6.6 (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H).
Weakness: CWE-1284. Red Hat lists Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9 as not affected.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · medium-confidence parse· fetched 1 hour ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · medium-confidence parse· fetched 1 hour ago·verify at source
Mitigation
The source record does not include mitigation steps. That is not a statement that no fix exists — read the vendor advisory below for the authoritative guidance.
Official advisory · medium-confidence parse· fetched 1 hour ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.