CVE-2021-27645
Publication date 24 February 2021
Last updated 25 August 2025
Ubuntu priority
Description
The nameserver caching daemon (nscd) in the GNU C Library (aka glibc or libc6) 2.29 through 2.33, when processing a request for netgroup lookup, may crash due to a double-free, potentially resulting in degraded service or Denial of Service on the local system. This is related to netgroupcache.c.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| eglibc | 24.04 LTS noble | Not in release |
| 22.04 LTS jammy | Not in release | |
| 20.04 LTS focal | Not in release | |
| 18.04 LTS bionic | Not in release | |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty |
Not affected
|
|
| glibc | 24.04 LTS noble |
Not affected
|
| 22.04 LTS jammy |
Not affected
|
|
| 20.04 LTS focal |
Fixed 2.31-0ubuntu9.7
|
|
| 18.04 LTS bionic |
Not affected
|
|
| 16.04 LTS xenial |
Not affected
|
|
| 14.04 LTS trusty | Not in release |
Notes
mdeslaur
introduced in 2.29 by: https://sourceware.org/git/?p=glibc.git;a=commit;h=745664bd798ec8fd50438605948eea594179fba1 introduced in 2.28-1 debian packaging by: https://salsa.debian.org/glibc-team/glibc/-/commit/aea56157b456d4d9bef337d0149e952a41a7d919
Patch details
| Package | Patch details |
|---|---|
| glibc |
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
2.5 · Low
|
| Attack vector | Local |
| Attack complexity | High |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | None |
| Availability impact | Low |
| Vector | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L |
References
Related Ubuntu Security Notices (USN)
- USN-5310-1
- GNU C Library vulnerabilities
- 1 March 2022