CVE-2026-39834 (GCVE-0-2026-39834)
Vulnerability from cvelistv5 – Published: 2026-05-22 02:31 – Updated: 2026-05-22 18:50
VLAI?
Title
Invoking infinite loop on large channel writes in golang.org/x/crypto/ssh
Summary
When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.
Severity ?
9.1 (Critical)
CWE
- CWE-190 - Integer Overflow or Wraparound
Assigner
References
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| golang.org/x/crypto | golang.org/x/crypto/ssh |
Affected:
0 , < 0.52.0
(semver)
|
Credits
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"name": "dhGEXSHA.Client"
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"name": "dhGEXSHA.Server"
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{
"name": "dhGroup.Client"
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{
"name": "dhGroup.Server"
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{
"name": "ecdh.Client"
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{
"name": "ecdh.Server"
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"name": "extChannel.Write"
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{
"name": "mlkem768WithCurve25519sha256.Client"
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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