Cyber Resilience

CVE-2021-26833

MediumPublic PoC

Published: 06 April 2021

Published
06 April 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0032 55.1th percentile
Risk Priority 12 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-26833 is a medium-severity Incomplete Cleanup (CWE-459) vulnerability in Timelybills Timelybills. Its CVSS base score is 5.9 (Medium).

Operationally, ranked in the top 44.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Cleartext Storage in a File or on Disk in TimelyBills <= 1.7.0 for iOS and versions <= 1.21.115 for Android allows attacker who can locally read user's files obtain JWT tokens for user's account due to insufficient cache clearing mechanisms.…

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A threat actor can obtain sensitive user data by decoding the tokens as JWT is signed and encoded, not encrypted.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

timelybills
timelybills
≤ 1.7.0 · ≤ 1.21.115

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-459

Mandates complete sanitization during cleanup so that shared resources (memory, caches, buffers) do not retain data across subjects.

addresses: CWE-459

Operational retention schedules mandate complete cleanup of temporary or residual sensitive data after use.

addresses: CWE-459

Termination of the non-persistent artifact guarantees cleanup of temporary state, directly countering incomplete cleanup weaknesses.

addresses: CWE-459

Fail-safe procedures can explicitly require cleanup of temporary state, resources, or privileges on failure to avoid leaving the system in an inconsistent state.

addresses: CWE-459

The explicit delete step when information is no longer needed implements the cleanup that this weakness omits.

addresses: CWE-459

Enforces complete cleanup and sanitization steps during disposal, closing gaps that leave data remnants on retired components.

References