GHSA-3m6f-3gfg-4x56
Panic on incorrect date input to `simple_asn1`
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
simple_asn1Real-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
Version 0.6.0 of the simple_asn1 crate panics on certain malformed
inputs to its parsing functions, including from_der and der_decode.
Because this crate is frequently used with inputs from the network, this
should be considered a security vulnerability.
The issue occurs when parsing the old ASN.1 "UTCTime" time format. If an
attacker provides a UTCTime where the first character is ASCII but the
second character is above 0x7f, a string slice operation in the
from_der_ function will try to slice into the middle of a UTF-8
character, and cause a panic.
This error was introduced in commit
d7d39d709577710e9dc8,
which updated simple_asn1 to use time instead of chrono because of
RUSTSEC-2020-159.
Versions of simple_asn1 before 0.6.0 are not affected by this issue.
The patch was applied in
simple_asn1 version 0.6.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | simple_asn1 | ≥ 0.6.0&&< 0.6.1 | 0.6.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for simple_asn1. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update simple_asn1 to 0.6.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-3m6f-3gfg-4x56 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-3m6f-3gfg-4x56 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-3m6f-3gfg-4x56. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-3m6f-3gfg-4x56 in your dependencies?
O3 detects GHSA-3m6f-3gfg-4x56 across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.