GHSA-fh2r-99q2-6mmg RUSTSEC-2023-0053
rustls-webpki: CPU denial of service in certificate path building
- Severity
- 7.5 / 10
- High · CVSS 3.0
- Exploit chance (EPSS)
- 6.48%
- Chance of exploitation in the next 30 days. Higher than 93.75% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-400 Uncontrolled Resource Consumption
- Fix
0.100.2- Upgrade rustls-webpki to this version or later
Description
When this crate is given a pathological certificate chain to validate, it will spend CPU time exponential with the number of candidate certificates at each step of path building.
Both TLS clients and TLS servers that accept client certificate are affected.
We now give each path building operation a budget of 100 signature verifications.
The original webpki crate is also affected, see GHSA-8qv2-5vq6-g2g7.
This was previously reported in the original crate https://github.com/briansmith/webpki/issues/69 and re-reported to us recently.
Affected versions
crates.io
| Package | Vulnerable | Fixed in |
|---|---|---|
| rustls-webpki | < 0.100.2 |
0.100.2 |
| rustls-webpki | >= 0.101.0, < 0.101.4 |
0.101.4 |
| rustls-webpki | >= 0.0.0-0, < 0.100.2>= 0.101.0, < 0.101.4 |
0.100.20.101.4 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
rustls-webpki crates.io → 0.100.2
- cargo
cargo update -p rustls-webpki --precise 0.100.2
Severity breakdown
CVSS 3.0 7.5
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Weakness
CWE-400: Uncontrolled Resource Consumption
The product does not properly control the allocation and maintenance of a limited resource.
How to prevent it
- Architecture and Design: Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place. The login application should be protected against DoS attacks as much as possible. Limiting the database access, perhaps by caching result sets, can help minimize the resources expended. To further limit the potential for a DoS attack, consider tracking the rate of requests received from users and blocking requests that exceed a defined rate threshold.
- Architecture and Design: Mitigation of resource exhaustion attacks requires that the target system either: recognizes the attack and denies that user further access for a given amount of time, or uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed. The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question. The second solution is simply difficult to effectively institute -- and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.
- Architecture and Design: Ensure that protocols have specific limits of scale placed on them.
- Implementation: Ensure that all failures in resource allocation place the system into a safe posture.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GO-2022-0191 Denial of service in chain verification in crypto/x509 | Not rated yet | Linked by the source |
| RUSTSEC-2026-0382 Distrust compromised intermediate certificates in crypto/x509 | Medium | Also affects rustls-webpki |
| GHSA-82j2-j2ch-gfr8 rustls-webpki: Denial of service via panic on malformed CRL BIT STRING | High | Also affects rustls-webpki |
| GHSA-xgp8-3hg3-c2mh webpki: Name constraints were accepted for certificates asserting a wildcard name | Low | Also affects rustls-webpki |
| GHSA-965h-392x-2mh5 webpki: Name constraints for URI names were incorrectly accepted | Low | Also affects rustls-webpki |
| GHSA-pwjx-qhcg-rvj4 webpki: CRLs not considered authoritative by Distribution Point due to faulty matching logic | Medium | Also affects rustls-webpki |
| GHSA-cggf-277g-3q54 pypdf has possible large memory usage when parsing page tree | High | Same weakness, CWE-400 |
| GHSA-3g3m-2fjr-6pw4 Glob: AbortSignal cancellation bypass allows post-timeout filesystem traversal | Medium | Same weakness, CWE-400 |
MergeHarbor checks every repository's dependencies against this database, ranks what matters by exploitability and reachability, routes it to the owning team and opens the fix pull request.
Check your repos with MergeHarbor