CVE-2026-39820
Quadratic string concatentation in consumeComment in net/mail
HIGH
7.5
CVSS Score
Published: May 7, 2026 at 07:41 PM UTC
Updated: October 26, 2026 at 12:10 AM UTC
35 products affected across 3 vendorsGoNet/mailEnterprise Linux
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Severity
HIGH7.5
Exploit prediction
EPSS 0.8%
SSVC
No known exploit
Description
Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
v < 1.25.101.26.0 ≤ v < 1.26.3
Affected range stops below 1.25.10, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.26.3, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.25.10, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.26.3, so it looks safe — our inference, not a vendor statement
Vendor states this is fixed in 2 (unaffected)
60%
All versions
60%
Vendor states this is fixed in 0:1.1.4-1.el10em (unaffected)
Vendor states this is fixed in 0:1.1.4-1.el9em (unaffected)
Vendor states this is fixed in 0:0.152.1-2.el10_0 (unaffected)
Vendor states this is fixed in 0:0.152.1-2.el10_2 (unaffected)
Vendor states this is fixed in 0:0.152.1-2.el9_4 (unaffected)
Vendor states this is fixed in 0:0.152.1-2.el9_6 (unaffected)
Vendor states this is fixed in 0:0.152.1-2.el9_8 (unaffected)
Vendor states this is fixed in 0:1.26.3-1.el9_8 (unaffected)
Vendor states this is fixed in 0:1.26.3-4.el10_2 (unaffected)
Vendor states this is fixed in 0:1.26.5-1.el10_0 (unaffected)
Vendor states this is fixed in 0:1.26.5-1.el9_2 (unaffected)
Vendor states this is fixed in 0:1.26.5-1.el9_4 (unaffected)
Vendor states this is fixed in 0:1.26.5-1.el9_6 (unaffected)
Vendor states this is fixed in 0:10.2.6-22.el9_6 (unaffected)
Vendor states this is fixed in 0:10.2.6-23.el9_8.3 (unaffected)
Vendor states this is fixed in 0:10.2.6-26.el10_0 (unaffected)
Vendor states this is fixed in 0:10.2.6-28.el10_2.5 (unaffected)
Vendor states this is fixed in 0:101.3-4.el9_4.6 (unaffected)
Vendor states this is fixed in 0:101.5-2.el8_10 (unaffected)
Vendor states this is fixed in 0:132.2-12.el9_6 (unaffected)
Vendor states this is fixed in 0:134.1-12.el10_0 (unaffected)
Vendor states this is fixed in 0:165.1-3.el10_2.2 (unaffected)
Vendor states this is fixed in 0:165.1-4.el9_8.1 (unaffected)
Vendor states this is fixed in 0:2.21.0-3.el10_0.4 (unaffected)
Vendor states this is fixed in 0:2.21.0-7.el9_6.1 (unaffected)
Vendor states this is fixed in 0:52.1-1.el10_2.2 (unaffected)
Vendor states this is fixed in 0:52.1-1.el9_8.2 (unaffected)
Vendor states this is fixed in 0:75-10.el8_8 (unaffected)
Vendor states this is fixed in 0:76.1-9.el9_2 (unaffected)
Vendor states this is fixed in 0:9.2.10-33.el8_10 (unaffected)
Vendor states this is fixed in 10 (unaffected)
Vendor states this is fixed in 8100020260518131104.a3795dee (unaffected)
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
References (97)
Issue TrackingMailing List
Source: cverecord
https://groups.google.com/g/golang-announce/c/qcCIEXso47MSource: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:33120Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:33123Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:33142Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:33150SSVC — Action Prioritization
SSVCNo known exploitAutomatablePartial impact
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
7.5HIGHCISA-ADP
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- NONE
- Integrity
- NONE
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-770CWE-606
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