Description
xbuf_format_converter, used as part of exif_read_data, was appending a terminating null character to the generated string, but was not using its standard append char function. As a result, if the buffer was full, it would result in an out-of-bounds write. This issue affects HHVM versions prior to 4.56.3, all versions between 4.57.0 and 4.80.1, all versions between 4.81.0 and 4.93.1, and versions 4.94.0, 4.95.0, 4.96.0, 4.97.0, 4.98.0.
Metrics
CVSS 3.1 9.8/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| HHVM | 4.98.0; 4.97.0; 4.96.0; 4.95.0; 4.94.0; >= 4.81.0, < unspecified; >= 4.57.0, < unspecified; >= unspecified, < 4.56.3 |
References
- https://github.com/facebook/hhvm/commit/08193b7f0cd3910256e00d599f0f3eb2519c44caPatch, Third Party Advisory
- https://hhvm.com/blog/2021/02/25/security-update.htmlRelease Notes, Vendor Advisory
- https://github.com/facebook/hhvm/commit/08193b7f0cd3910256e00d599f0f3eb2519c44caPatch, Third Party Advisory
- https://hhvm.com/blog/2021/02/25/security-update.htmlRelease Notes, Vendor Advisory
Timeline
- Published
- Mar 10, 2021
- Last modified
- Jun 17, 2026
- NVD status
- Modified