Candidate: CVE-2020-26243
PublicDate: 2020-11-25 17:15:00 UTC
References:
 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26243
 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
Description:
 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.
Ubuntu-Description:
Notes:
Mitigation:
Bugs:
 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=975838
Priority: medium
Discovered-by:
Assigned-to:
CVSS:
 nvd: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H [7.5 HIGH]


Patches_nanopb:
upstream_nanopb: released (0.3.9.7, 0.4.4)
precise/esm_nanopb: DNE
trusty_nanopb: ignored (out of standard support)
trusty/esm_nanopb: DNE
xenial_nanopb: DNE
bionic_nanopb: DNE
focal_nanopb: needed
groovy_nanopb: ignored (reached end-of-life)
hirsute_nanopb: not-affected (0.4.4-1)
impish_nanopb: not-affected (0.4.4-1)
jammy_nanopb: not-affected (0.4.4-1)
devel_nanopb: not-affected (0.4.4-1)