CVE-2026-68511
Paaster: TOCTOU race condition defeats the 'burn after reading' guarantee on view-once pastes
- Medium 6.3
Description
Paaster is a pastebin application. Prior to version 3.3.0, Paaster's "view once" (burn-after-reading) paste mode can be bypassed with concurrent requests. The check that's supposed to enforce single-use is a plain read followed by a separate write, with no atomicity, so multiple simultaneous requests can all see the paste as "not yet read" and all successfully retrieve it. This issue has been patched in version 3.3.0.
Key facts
- Published
- 11 Nov 2026
- Last changed
- 13 Nov 2026
- Assigned by
- GitHub_M
- EPSS
- 0.349% likely to be exploited in the next 30 days, higher than 28.973% of CVEs (scores for 15 Nov 2026)
- SSVC (CISA)
- Exploitation: poc; Automatable: no; Technical impact: partial
Severity scores
Each score is shown as its source gave it. They are not averaged or merged.
- 6.3CVSS 4.0, Mediumfrom the CNA (GitHub_M)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Historical context and remediation
This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.
No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.
No explicit remediation statement is available on this page yet. Consult the original record and vendor references before choosing a fix.
Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.
Affected products
| Vendor | Product | Versions |
|---|---|---|
| WardPearce | paaster |
|
Timeline
- 11 Nov 2026 Published