CVE-2019-25035

Memory corruption via unchecked parenthesized newline handling

Published Apr 27, 2021 · Updated Aug 5, 2024

An out-of-bounds write in sldns_bget_token_par affects NLnet Labs Unbound before 1.9.5 during buffered token parsing. The parser replaces a parenthesized newline with a space by advancing the token pointer without first checking the supplied buffer limit. NLnet Labs disputes the vulnerability because a running Unbound installation cannot reach the defective path through remote or local input.

CVSS severity9.8
Critical
EPSS probability2.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

An out-of-bounds write in sldns_bget_token_par affects NLnet Labs Unbound before 1.9.5 during buffered token parsing. The parser replaces a parenthesized newline with a space by advancing the token pointer without first checking the supplied buffer limit. NLnet Labs disputes the vulnerability because a running Unbound installation cannot reach the defective path through remote or local input.

The record

CVE
CVE-2019-25035
Published
Apr 27, 2021
Updated
Aug 5, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Apr 27, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS: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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write

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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