CVE-2021-29948

Exp

Signatures are written to disk before and read during verification, which might be subject to a race condition when a malicious local process or user is replacing the file. This vulnerability affects Thunderbird < 78.10.

Published: 2021-06-24 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-29948 is rated Exploit Available (50/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.29%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-29948

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-29948

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.03% 0.29% +0.25%
2 2026-06-08 0.07% 0.03% -0.04%
3 2025-11-21 — 0.07% —

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-29948

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
2.5 3.1 LOW
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 1.0 1.4 [email protected]
1.9 2.0 LOW
AV:L/AC:M/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 3.4 2.9 [email protected]

Weakness enumeration for CVE-2021-29948

OS Trackers for CVE-2021-29948

vendor priority summary link
alpine low CVE-2021-29948: 1 source package rows (thunderbird); 27 state rows across 7 repos (3.17-community, 3.18-community, 3.19-community, 3.20-community, 3.21-community, 3.22-community, edge-community); fixed 7, open 20. https://security.alpinelinux.org/vuln/CVE-2021-29948
debian not yet assigned CVE-2021-29948 not yet assigned priority: Debian including 1 source packages (thunderbird), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-29948
gentoo normal CVE-2021-29948: 1 GLSA(s) (202104-09), 2 atom(s) (mail-client/thunderbird, mail-client/thunderbird-bin); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2021-29948
redhat low — https://access.redhat.com/security/cve/CVE-2021-29948
suse high CVE-2021-29948 severity important: SUSE including 17 source package names (MozillaThunderbird-78.10.0-8.23.1, MozillaThunderbird-78.10.0-bp153.1.1, …), 54 product×package rows across 21 product lines (SUSE Liberty Linux 7, SUSE Liberty Linux 8, … (21 product lines)): Fixed 54. https://www.suse.com/security/cve/CVE-2021-29948/
ubuntu low CVE-2021-29948 low priority: Ubuntu including 1 source packages (thunderbird), 11 status rows across 11 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, trusty, upstream, xenial): released 9, DNE 1, ignored 1. https://ubuntu.com/security/CVE-2021-29948

Affected software / configurations for CVE-2021-29948

Vendor Product Version Raw CPE
mozilla thunderbird < 78.10 cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

References for CVE-2021-29948

URL Tags
https://bugzilla.mozilla.org/show_bug.cgi?id=1692899 Exploit Patch Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-14/ Release Notes Vendor Advisory
cvelogic Threat Intelligence