CVE-2024-53861 | Issuer field partial matches allowed in pyjwt

Exp

pyjwt is a JSON Web Token implementation in Python. An incorrect string comparison is run for `iss` checking, resulting in `"acb"` being accepted for `"_abc_"`. This is a bug introduced in version 2.10.0: checking the "iss" claim changed from `isinstance(issuer, list)` to `isinstance(issuer, Sequence)`. Since str is a Sequnce, but not a list, `in` is also used for string comparison. This results in `if "abc" not in "__abcd__":` being checked instead of `if "abc" != "__abc__":`. Signature checks are still present so real world impact is likely limited to denial of service scenarios. This issue has been patched in version 2.10.1. All users are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2024-11-29 Last update: 2025-09-22 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-53861 is rated Exploit Available (51.1/100): CVSS Low severity, with medium exploitation likelihood (EPSS 1.02%). 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-2024-53861

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

Exploit prediction scoring system (EPSS) score for CVE-2024-53861

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 2026-03-24 0.69% 1.02% +0.33%
2 2026-01-07 0.08% 0.69% +0.62%
3 2025-11-21 — 0.08% —

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-53861

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
2.2 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
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.
 0.7 1.4 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
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:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2024-53861

GitHub Security Advisory for CVE-2024-53861

GHSA-75c5-xw7c-p5pm · Severity: low · Ecosystem: pip — PyJWT Issuer field partial matches allowed

OS Trackers for CVE-2024-53861

vendor priority summary link
debian unimportant CVE-2024-53861 unimportant priority: Debian including 1 source packages (pyjwt), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2024-53861
redhat low — https://access.redhat.com/security/cve/CVE-2024-53861
ubuntu medium CVE-2024-53861 medium priority: Ubuntu including 1 source packages (pyjwt), 7 status rows across 7 suites (bionic, focal, jammy, noble, oracular, upstream, xenial): not-affected 7. https://ubuntu.com/security/CVE-2024-53861

Affected software / configurations for CVE-2024-53861

Vendor Product Version Raw CPE
pyjwt_project pyjwt 2.10.0 cpe:2.3:a:pyjwt_project:pyjwt:2.10.0:*:*:*:*:*:*:*

References for CVE-2024-53861

cvelogic Threat Intelligence