CVE-2024-53857 — pgp
HIGHCVE-2024-53857 is a high-severity (CVSS 7.5) vulnerability in pgp. A fix is available for pgp — see the affected versions and patch details below.
rPGP Potential Resource Exhaustion when handling Untrusted Messages
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-53857.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2024-53857 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 379,842 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
pgpReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
During a security audit, Radically Open Security discovered two vulnerabilities which allow attackers to trigger resource exhaustion vulnerabilities in rpgp by providing crafted messages. This affects general message parsing and decryption with symmetric keys.
Impact
Affected rpgp versions do not correctly set upper limits on the total reserved amount of memory when parsing long sequences of partial OpenPGP packets, which can grow to to several GiB in size. Additionally, up to 4GiB of memory is reserved for OpenPGP packets of fixed size with large length fields, even if less data is received.
Depending on existing message size restrictions and available system resources, this can cause out-of-memory conditions and crash the rpgp process or cause other system instability through memory resource exhaustion when parsing crafted messages.
Affected rpgp versions are susceptible to excessive memory allocation with values of up to 2TiB or long processing times for some decryption operations which involve the Argon2 function. An attacker can provide a valid Symmetric Key Encrypted Session Key packet (SKESK) which uses Argon2 for String-to-Key hashing with parameters that are excessive, but within specification limits of the RFC9580 OpenPGP standard. Since rpgp did not further restrict the Argon2 parameters, this can cause out-of-memory conditions and crash the rpgp process. Under some conditions, the memory resource exhaustion may trigger other system instability. Alternatively, this can make the program unresponsive via long computations. The attacker needs to trick a victim into attempting decryption, but does not require knowledge of the symmetric secret used by the victim.
There is no impact to confidentiality or integrity security properties.
Versions and Patches
The impact details on the message parsing component varies with different versions. We've confirmed some of the problematic behavior on older versions such as v0.10.0 and see all recent versions as affected in some form.
The affected Argon2 functionality was introduced with v0.12.0-alpha.1, earlier versions are not vulnerable.
The vulnerabilities have been fixed with version 0.14.2. We recommend all users to upgrade to this version.
References
The security audit was made possible by the NLnet Foundation NGI Zero Core grant program for rpgp.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | pgp | all versions | 0.14.2cargo update -p pgp --precise 0.14.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pgp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update pgp to 0.14.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-53857 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
Frequently Asked Questions
Is CVE-2024-53857 in your dependencies?
Find it across crates.io, including transitive dependencies.