How severe is GHSA-pwfw-mgfj-7g3g?

GHSA-pwfw-mgfj-7g3g has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-pwfw-mgfj-7g3g?

GHSA-pwfw-mgfj-7g3g affects the following packages: ecdsa (PyPI). Ecosystems affected: PyPI.

How do I fix GHSA-pwfw-mgfj-7g3g?

Update ecdsa to 0.13.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-pwfw-mgfj-7g3g is resolved across your whole dependency graph.

How do I detect GHSA-pwfw-mgfj-7g3g in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ecdsa, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-pwfw-mgfj-7g3g if there is no patch (or I can't update yet)?

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.

Is GHSA-pwfw-mgfj-7g3g actively exploited in the wild?

No public exploit code has been indexed for GHSA-pwfw-mgfj-7g3g yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-pwfw-mgfj-7g3g?

GHSA-pwfw-mgfj-7g3g has an EPSS (Exploit Prediction Scoring System) score of 2.4%, placing it in the 84th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-pwfw-mgfj-7g3g?

GHSA-pwfw-mgfj-7g3g is classified as CWE-391 (CWE-391), CWE-755 (CWE-755). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-pwfw-mgfj-7g3g published, and has it been updated?

GHSA-pwfw-mgfj-7g3g was published on October 8, 2019 and was last updated on September 20, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍

🐍 PyPI

Not in CISA KEV

HIGH severity

ecdsa Denial of Service vulnerability in signature verification and signature malleabilityGHSA-pwfw-mgfj-7g3g

HIGH

GHSA-pwfw-mgfj-7g3g is a high-severity (CVSS 7.5) CWE-391 vulnerability in ecdsa. A fix is available for ecdsa — see the affected versions and patch details below.

Also known asCVE-2019-14853 GHSA-2mrj-435v-c2crPYSEC-2019-177

Published

Oct 8, 2019

Updated

Sep 20, 2024

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 6, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

2.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs84th percentile — riskier than 84% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🐍ecdsa

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

possible DoS in signature verification and signature malleability

Impact

Code using VerifyingKey.verify() and VerifyingKey.verify_digest() may receive exceptions other than the documented BadSignatureError when signatures are malformed. If those other exceptions are not caught, they may lead to program termination and thus Denial of Service

Code using VerifyingKey.verify() and VerifyingKey.verify_digest() with sigdecode option using ecdsa.util.sigdecode_der will accept signatures even if they are not properly formatted DER. This makes the signatures malleable. It impacts only applications that later sign the signatures or verify signatures of signatures, e.g. Bitcoin.

All versions between 0.5 and 0.13.2 (inclusive) are thought to be vulnerable. Code before 0.5 may be vulnerable but didn't receive extended analysis to rule this issue out.

Patches

The patches have been merged to master branch in https://github.com/warner/python-ecdsa/pull/115. The backported patches for a release in the 0.13 branch are in https://github.com/warner/python-ecdsa/pull/124

They are part of the 0.13.3 release.

There are no plans to backport them to earlier releases.

Workarounds

It may be possible to prevent the Denial of Service by catching also UnexpectedDER, IndexError and AssertionError exceptions. That list hasn't been verified to be complete though. If those exceptions are raised, the signature verification process should consider the signature to be invalid.

To remediate signature malleability and the Denial of Service vulnerability, it may be possible to first verify that the signature is properly DER formatted ECDSA-Sig-Value, as defined in RFC3279, before passing it to verify() or verify_digest() methods. If the signature is determined to not follow the DER or encode a different structure, the signature verification process should consider the signature to be invalid.

References

https://en.bitcoinwiki.org/wiki/Transaction_Malleability

For more information

If you have any questions or comments about this advisory please open an issue in python-ecdsa project.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`ecdsa`	all versions	0.13.3`pip install --upgrade 'ecdsa==0.13.3'`

Affected Products

1 product · 1 configurations

Application

python-ecdsapython-ecdsa_project

< 0.13.3

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ecdsa, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ecdsa to 0.13.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-pwfw-mgfj-7g3g 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.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatLow

Although Red Hat OpenStack Platform ships the flawed code, RHOSP does not actually use python-ecdsa's functionality. As such, Red Hat OpenStack Platform will not be providing a fix for python-ecdsa at this time. Current releases of Red Hat Virtualization Manager no longer includes python-ecdsa as a dependency. While…

Product	Fixed in	Advisory
Red Hat Satellite 6.10 for RHEL 7	`python-ecdsa-0:0.13.3-2.el7pc`	RHSA-2021:4702

Frequently Asked Questions

## possible DoS in signature verification and signature malleability ### Impact Code using `VerifyingKey.verify()` and `VerifyingKey.verify_digest()` may receive exceptions other than the documented `BadSignatureError` when signatures are malformed. If those other exceptions are not caught, they may lead to program termination and thus Denial of Service Code using `VerifyingKey.verify()` and `VerifyingKey.verify_digest()` with `sigdecode` option using `ecdsa.util.sigdecode_der` will accept signatures even if they are not properly formatted DER. This makes the signatures malleable. It impact