Pow Mnesia cache doesn't invalidate all expired keys on startupGHSA-3cjh-p6pw-jhv9
MEDIUMFix: pow-auth/pow#714GHSA-3cjh-p6pw-jhv9 is a medium-severity (CVSS 6.5) CWE-298 vulnerability in pow. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for pow — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- 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 GHSA-3cjh-p6pw-jhv9.
EPSS Exploitation Probability
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
powReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Hex packages — download data is not available via public APIs for these ecosystems.
Description
Use of Pow.Store.Backend.MnesiaCache is susceptible to session hijacking as expired keys are not being invalidated correctly on startup. A cache key may become expired when all Pow.Store.Backend.MnesiaCache instances have been shut down for a period that is longer than the keys' remaining TTL and the expired key won't be invalidated on startups.
Workarounds
The expired keys, including all expired sessions, can be manually invalidated by running:
:mnesia.sync_transaction(fn ->
Enum.each(:mnesia.dirty_select(Pow.Store.Backend.MnesiaCache, [{{Pow.Store.Backend.MnesiaCache, :_, :_}, [], [:"$_"]}]), fn {_, key, {_value, expire}} ->
ttl = expire - :os.system_time(:millisecond)
if ttl < 0, do: :mnesia.delete({Pow.Store.Backend.MnesiaCache, key})
end)
end)
References
https://github.com/pow-auth/pow/commit/15dc525be03c466daa5d2119ca7acdec7b24ed17 https://github.com/pow-auth/pow/issues/713 https://github.com/pow-auth/pow/pull/714
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💧Hex | pow | ≥ 1.0.14&&< 1.0.34 | 1.0.34mix deps.update pow |
Affected Products
powpowauthResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pow, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update pow to 1.0.34 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-3cjh-p6pw-jhv9 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.
Frequently Asked Questions
Is GHSA-3cjh-p6pw-jhv9 in your dependencies?
Find it across Hex, including transitive dependencies.