PatchTheCVECVE-2020-1897: A use-after-free is possible due to an error in lifetime management in the request adaptor when a malicious cl
CVE-2020-1897 is a critical-severity flaw (CVSS 9.8) affecting proxygen. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A use-after-free is possible due to an error in lifetime management in the request adaptor when a malicious client invokes request error handling in a specific sequence. This issue affects versions of proxygen prior to v2020.05.18.00.
Why this priority
- Critical severity
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 1.1% (top 33%) |
| CISA exploited list | No |
| Weakness | CWE-416 |
| Published | 2020-05-18 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2020-1897?
proxygen: upgrade to 2020.05.18.00. Exact commands for each OS are on this page.
Is CVE-2020-1897 being exploited?
CVE-2020-1897 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2020-1897 affect?
CVE-2020-1897 affects proxygen. Severity is critical (CVSS 9.8). A use-after-free is possible due to an error in lifetime management in the request adaptor when a malicious client invokes request error handling in a specific sequence. This issue affects versions of proxygen prior to v2020.05.18.00.
How urgent is CVE-2020-1897?
Priority 56/100. Critical severity; Remotely exploitable, no login, no user action
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