CVE-2020-1897Network attack vector

Invalid memory access via request adaptor lifetime error

Published May 18, 2020 · Updated Aug 4, 2024

Use-after-free in Proxygen before 2020.05.18.00 allows remote attackers to trigger invalid memory access via crafted error sequences. The request adaptor mishandles object lifetime when request-error handling occurs in a specific sequence, leaving freed storage reachable. Unauthenticated network access to a service built with the affected library is sufficient; the vendor has not disclosed a deterministic process consequence.

CVSS severity9.8
Critical
EPSS probability1.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Proxygen before 2020.05.18.00 allows remote attackers to trigger invalid memory access via crafted error sequences. The request adaptor mishandles object lifetime when request-error handling occurs in a specific sequence, leaving freed storage reachable. Unauthenticated network access to a service built with the affected library is sufficient; the vendor has not disclosed a deterministic process consequence.

The record

CVE
CVE-2020-1897
Published
May 18, 2020
Updated
Aug 4, 2024
Vendor
Meta Platforms, Inc.
Product
Proxygen
Classifications
CWE-416, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 18, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <v2020.05.18.00

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Meta Platforms, Inc. · Proxygenversion=unspecified <v2020.05.18.00

Published CVSS scores

7.5NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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