CVE-2020-15904
A buffer overflow in the patching routine of bsdiff4 before 1.2.0 allows an attacker to write to heap memory (beyond allocated bounds) via a crafted patch file.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.05%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A buffer overflow in the patching routine of bsdiff4 before 1.2.0 allows an attacker to write to heap memory (beyond allocated bounds) via a crafted patch file.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- EPSS
- 1.05% probability · 64th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Affected
- pypi/bsdiff4
- Source
- cve@mitre.org
EPSS 1.1% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/ilanschnell/bsdiff4/blob/master/CHANGELOG.txtRelease Notes, Third Party Advisory
- https://github.com/ilanschnell/bsdiff4/commit/49a4cee2feef7deaf9d89e5e793a8824930284d7Patch, Third Party Advisory
- https://github.com/ilanschnell/bsdiff4/blob/master/CHANGELOG.txtRelease Notes, Third Party Advisory
- https://github.com/ilanschnell/bsdiff4/commit/49a4cee2feef7deaf9d89e5e793a8824930284d7Patch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.