CVE-2022-21688Network attack vector

Memory exhaustion via unsanitized history path rendering

Published Jan 18, 2022 · Updated Apr 23, 2025

Denial of service in OnionShare before 2.5 allows remote attackers to exhaust desktop memory through a crafted history path. The history item widget passes the path parameter into Qt image rendering without first sanitizing it to plain text, so roughly 20 input bytes can allocate about 2 GB repeatedly. The attacker must know the onion address and use a public service or valid private-service authentication, and a user must display history; success drives the hosting desktop process out of memory.

CVSS severity5.5
Medium
EPSS probability0.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in OnionShare before 2.5 allows remote attackers to exhaust desktop memory through a crafted history path. The history item widget passes the path parameter into Qt image rendering without first sanitizing it to plain text, so roughly 20 input bytes can allocate about 2 GB repeatedly. The attacker must know the onion address and use a public service or valid private-service authentication, and a user must display history; success drives the hosting desktop process out of memory.

The record

CVE
CVE-2022-21688
Published
Jan 18, 2022
Updated
Apr 23, 2025
Vendor
OnionShare
Product
OnionShare
Classifications
CWE-125, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 18, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 2025Record 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=< 2.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OnionShare · OnionShareversion=< 2.5

Published CVSS scores

6.8NISTAV:N/AC:M/Au:N/C:N/I:N/A:P
5.5NISTCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read
T1499.003Application Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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