CVE-2020-26243
Publication date 25 November 2020
Last updated 24 July 2024
Ubuntu priority
Cvss 3 Severity Score
Nanopb is a small code-size Protocol Buffers implementation. In Nanopb before versions 0.4.4 and 0.3.9.7, decoding specifically formed message can leak memory if dynamic allocation is enabled and an oneof field contains a static submessage that contains a dynamic field, and the message being decoded contains the submessage multiple times. This is rare in normal messages, but it is a concern when untrusted data is parsed. This is fixed in versions 0.3.9.7 and 0.4.4. The following workarounds are available: 1) Set the option `no_unions` for the oneof field. This will generate fields as separate instead of C union, and avoids triggering the problematic code. 2) Set the type of the submessage field inside oneof to `FT_POINTER`. This way the whole submessage will be dynamically allocated and the problematic code is not executed. 3) Use an arena allocator for nanopb, to make sure all memory can be released afterwards.
Status
Package | Ubuntu Release | Status |
---|---|---|
nanopb | 24.10 oracular |
Not affected
|
24.04 LTS noble |
Not affected
|
|
22.04 LTS jammy |
Not affected
|
|
20.04 LTS focal |
Fixed 0.4.1-1ubuntu0.1~esm1
|
|
18.04 LTS bionic | Not in release | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release |
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Get Ubuntu ProSeverity score breakdown
Parameter | Value |
---|---|
Base score | 7.5 · High |
Attack vector | Network |
Attack complexity | Low |
Privileges required | None |
User interaction | None |
Scope | Unchanged |
Confidentiality | None |
Integrity impact | None |
Availability impact | High |
Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
References
Related Ubuntu Security Notices (USN)
- USN-6121-1
- Nanopb vulnerabilities
- 30 May 2023
Other references
- https://github.com/nanopb/nanopb/security/advisories/GHSA-85rr-4rh9-hhwh
- https://github.com/nanopb/nanopb/commit/edf6dcbffee4d614ac0c2c1b258ab95185bdb6e9 (0.4.4)
- https://github.com/nanopb/nanopb/issues/615
- https://github.com/nanopb/nanopb/blob/2b48a361786dfb1f63d229840217a93aae064667/CHANGELOG.txt
- https://github.com/nanopb/nanopb/commit/4fe23595732b6f1254cfc11a9b8d6da900b55b0c
- https://www.cve.org/CVERecord?id=CVE-2020-26243