High [CVE-2026-102555] Libsoup: libsoup: heap buffer overflow via uninitialized length in data-uri base64 decoding
This high-severity Red Hat Linux advisory covers CVE-2026-102555 affecting Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 9.
Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.
VulniPulse record published
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
A flaw was found in libsoup. The soup_uri_decode_data_uri() function incorrectly treated base64 data-URI payloads as NUL-terminated strings when calling g_base64_decode_inplace().
If the percent-decoded payload contained embedded NUL bytes, the decoded length could remain uninitialized and be used as the size of the returned GBytes. This can lead to an out-of-bounds read or application crash when processing a crafted data URI.
This issue is rated Important. Impact depends on how the application consumes the returned GBytes.
Red Hat Enterprise Linux ships libsoup/libsoup3 widely used by GNOME and other HTTP clients; applications that decode untrusted data URIs are in scope. Red Hat severity: Important — CVSS 8.2 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H).
Weakness: CWE-125. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 9.
Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE.
Affected products named by the advisory: Red Hat package: libsoup3.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · high-confidence parse· fetched 1 day 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 · high-confidence parse· fetched 1 day ago·verify at source
Mitigation checklist
- To mitigate this do not pass untrusted data URIs to soup_uri_decode_data_uri().
Official advisory · high-confidence parse· fetched 1 day 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.