CVE-2020-5235
Out-of-memory condition in Nanopb is potentially exploitable
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
There is a potentially exploitable out of memory condition In Nanopb before 0.4.1, 0.3.9.5, and 0.2.9.4. When nanopb is compiled with PB_ENABLE_MALLOC, the message to be decoded contains a repeated string, bytes or message field and realloc() runs out of memory when expanding the array nanopb can end up calling `free()` on a pointer value that comes from uninitialized memory. Depending on platform this can result in a crash or further memory corruption, which may be exploitable in some cases. This problem is fixed in nanopb-0.4.1, nanopb-0.3.9.5, nanopb-0.2.9.4.
Timeline
ID reserved
By GitHub_M
- 33 days later
· 33 days later
Published
- 5 years later
· 5 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:L |
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 1.7% · top 22% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.
Weakness
Affected products
References (4)
- https://github.com/nanopb/nanopb/security/advisories/GHSA-gcx3-7m76-287p (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/nanopb/nanopb/commit/45582f1f97f49e2abfdba1463d1e1027682d9856 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/nanopb/nanopb/commit/7b396821ddd06df8e39143f16e1dc0a4645b89a3 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/nanopb/nanopb/commit/aa9d0d1ca78d6adec3adfeecf3a706c7f9df81f2 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-5235)Record last updated .