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CVE Record

CVE-2025-9900: Libtiff: libtiff write-what-where

A flaw was found in Libtiff. This vulnerability is a "write-what-where" condition, triggered when the library processes a specially crafted TIFF image file. By providing an abnormally large image height value in the file's metadata, an attacker can trick the library into writing attacker-controlled color data to an arbitrary memory location. This memory corruption can be exploited to cause a denial of service (application crash) or to achieve arbitrary code execution with the permissions of the user.

HighCVSS 8.8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2025-9900 is a high-severity libtiff memory corruption flaw. A malicious TIFF image can trigger an arbitrary memory write when processed, potentially crashing the application or running code with the affected user’s privileges. Business risk is highest where servers or desktops automatically process untrusted image files.

Executive priority

Treat as high priority where TIFF files cross trust boundaries. It is not marked as actively exploited in the supplied sources, but the potential impact includes code execution. Patch affected Red Hat packages through normal emergency or accelerated maintenance processes.

Technical view

The flaw is described as CWE-123 write-what-where in libtiff. A crafted TIFF with an abnormally large image height can cause attacker-controlled color data to be written to an arbitrary memory location. CVSS 3.1 is 8.8 with network attack vector, low complexity, no privileges, and user interaction required.

Likely exposure

Exposure is likely on Red Hat systems carrying affected libtiff-related packages, including RHEL 10, RHEL 8 streams, RHEL 7 ELS, and listed support variants. Relevant package names include libtiff, compat-libtiff3, mingw-libtiff, and spice-client-win.

Exploitation context

The source bundle does not show CISA KEV listing or cited evidence of active exploitation. Practical exposure depends on whether affected software processes attacker-supplied TIFF files, such as uploads, email attachments, shared folders, document pipelines, or image conversion workflows.

Researcher notes

Evidence is strongest for Red Hat-packaged libtiff exposure. The bundle identifies affected package versions and advisories but does not provide exploit maturity, proof-of-concept status, or upstream patch details. Avoid assuming all libtiff deployments are affected without vendor confirmation.

Mitigation direction

  • Apply the relevant Red Hat security advisories for affected libtiff-related packages.
  • Prioritize systems that process untrusted or external TIFF image files.
  • Restrict TIFF upload or processing paths until vendor updates are installed.
  • Run image-processing services with least privilege and isolation.
  • Check vendor guidance for non-Red Hat libtiff builds or bundled copies.

Validation and detection

  • Inventory installed libtiff, compat-libtiff3, mingw-libtiff, and spice-client-win packages.
  • Map image-processing applications that accept TIFF files from users or external sources.
  • Confirm patched package versions against the applicable Red Hat advisory.
  • Review logs for crashes in services that parse TIFF images.
  • Identify statically bundled libtiff copies in third-party applications.
Prepared
Confidence
high
Sources
12

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-123: Exact CWE lookup

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description · low confidence lookup

Execution behavior lookup

The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

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cve · low confidence lookup

CVE-2025-9900 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
High
CVSS
8.8 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
5Timeline events
2ADP providers
39Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: pocAutomatable: noTechnical Impact: total

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
8.8CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H2.85.9redhat

Vulnerability scoring details

Base CVSS 3.1 score

8.8High
CVSS 3.1 vector shape for CVE-2025-9900Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. Source timelineredhat

    Reported to Red Hat.

  2. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  3. Source timelineredhat

    Made public.

  4. CVE publishedCVE Program

    The CVE record was published.

  5. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc
CVECVE Program Container

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
Unknown vendorlibtifflibtiff, 0unaffected
Red HatRed Hat Enterprise Linux 10libtiff, 0:4.6.0-6.el10_0.1affected
Red HatRed Hat Enterprise Linux 10libtiff, 0:4.6.0-6.el10_1.1affected
Red HatRed Hat Enterprise Linux 7 Extended Lifecycle Supportcompat-libtiff3, 0:3.9.4-12.el7_9.1affected
Red HatRed Hat Enterprise Linux 7 Extended Lifecycle Supportlibtiff, 0:4.0.3-35.el7_9.1affected
Red HatRed Hat Enterprise Linux 8compat-libtiff3, 0:3.9.4-14.el8_10affected
Red HatRed Hat Enterprise Linux 8libtiff, 0:4.0.9-35.el8_10affected
Red HatRed Hat Enterprise Linux 8mingw-libtiff, 0:4.0.9-3.el8_10affected
Red HatRed Hat Enterprise Linux 8.2 Advanced Update Supportcompat-libtiff3, 0:3.9.4-13.el8_2.1affected
Red HatRed Hat Enterprise Linux 8.2 Advanced Update Supportlibtiff, 0:4.0.9-17.el8_2.1affected
Red HatRed Hat Enterprise Linux 8.2 Advanced Update Supportspice-client-win, 0:8.10-3.el8_2.1affected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Supportcompat-libtiff3, 0:3.9.4-13.el8_4.1affected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Supportlibtiff, 0:4.0.9-18.el8_4.1affected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Supportspice-client-win, 0:8.10-3.el8_4.1affected
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-Oncompat-libtiff3, 0:3.9.4-13.el8_4.1affected
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-Onlibtiff, 0:4.0.9-18.el8_4.1affected
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-Onspice-client-win, 0:8.10-3.el8_4.1affected
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Supportcompat-libtiff3, 0:3.9.4-13.el8_6.1affected
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Supportlibtiff, 0:4.0.9-21.el8_6.1affected
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Supportspice-client-win, 0:8.10-3.el8_6.1affected
Red HatRed Hat Enterprise Linux 8.6 Telecommunications Update Servicecompat-libtiff3, 0:3.9.4-13.el8_6.1affected
Red HatRed Hat Enterprise Linux 8.6 Telecommunications Update Servicelibtiff, 0:4.0.9-21.el8_6.1affected
Red HatRed Hat Enterprise Linux 8.6 Telecommunications Update Servicespice-client-win, 0:8.10-3.el8_6.1affected
Red HatRed Hat Enterprise Linux 8.6 Update Services for SAP Solutionscompat-libtiff3, 0:3.9.4-13.el8_6.1affected
Red HatRed Hat Enterprise Linux 8.6 Update Services for SAP Solutionslibtiff, 0:4.0.9-21.el8_6.1affected
Red HatRed Hat Enterprise Linux 8.6 Update Services for SAP Solutionsspice-client-win, 0:8.10-3.el8_6.1affected
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update Servicecompat-libtiff3, 0:3.9.4-13.el8_8.1affected
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update Servicelibtiff, 0:4.0.9-29.el8_8.1affected
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update Servicespice-client-win, 0:8.10-3.el8_8.1affected
Red HatRed Hat Enterprise Linux 8.8 Update Services for SAP Solutionscompat-libtiff3, 0:3.9.4-13.el8_8.1affected
Weakness

CWE details

CWE-123

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-123 · source CWE mapping

Write-what-where Condition

Write-what-where Condition represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

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