CVE-2021-45960
Published: August 31, 2023Last modified: July 22, 2025
Description
In Expat (aka libexpat) before 2.4.3, a left shift by 29 (or more) places in the storeAtts function in xmlparse.c can lead to realloc misbehavior (e.g., allocating too few bytes, or only freeing memory).
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 8.8 |
| Attack Vector | NETWORK |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | expat | Not affected (2.5.0-r0) |
| Stream | expat | Not affected (2.5.0-r2) | |
| Hardened Containers | 23 LTS | expat | Not affected (2.5.0-r0) |
| Stream | expat | Not affected (2.5.0-r2) |
References
- http://www.openwall.com/lists/oss-security/2022/01/17/3
- https://bugzilla.mozilla.org/show_bug.cgi?id=1217609
- https://cert-portal.siemens.com/productcert/pdf/ssa-484086.pdf
- https://github.com/libexpat/libexpat/issues/531
- https://github.com/libexpat/libexpat/pull/534
- https://security.gentoo.org/glsa/202209-24
- https://security.netapp.com/advisory/ntap-20220121-0004/
- https://www.debian.org/security/2022/dsa-5073
- https://www.tenable.com/security/tns-2022-05