Uninitialized memory disclosure and out-of-bounds read in POP3 and SMTP NTLM authentication
When authenticating to a POP3 or SMTP server using NTLM, Thunderbird did not check whether the server's challenge was valid base64. A malicious server could send a challenge that caused Thunderbird to include uninitialized heap memory in its NTLM response, disclosing that memory to the server. A challenge consisting only of base64 padding also caused an out-of-bounds read, crashing Thunderbird. This affected accounts configured to use NTLM or GSSAPI authentication. The uninitialized memory disclosure only affected NTLM. This vulnerability was fixed in Thunderbird 158.0.1 and Thunderbird 153.5.1.
CVE-2026-113868
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-113868
Thunderbird
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "Mozilla",
"product": "Thunderbird",
"versions": [
{
"status": "unaffected",
"version": "153.5.1",
"versionType": "rpm",
"lessThanOrEqual": "153.*"
},
{
"status": "unaffected",
"version": "158.0.1",
"versionType": "rpm",
"lessThanOrEqual": "*"
}
]
}
]- Related CVEs
- CVE-2026-113868
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #42590 · Revision 1
- Added to Heist Feed
- Publisher date