LiveActive security incident?Get immediate response
CVE Record

CVE-2026-31938: jsPDF has HTML Injection in New Window paths

jsPDF is a library to generate PDFs in JavaScript. Prior to version 4.2.1, user control of the `options` argument of the `output` function allows attackers to inject arbitrary HTML (such as scripts) into the browser context the created PDF is opened in. The vulnerability can be exploited in the following scenario: the attacker provides values for the output options, for example via a web interface. These values are then passed unsanitized (automatically or semi-automatically) to the attack victim. The victim creates and opens a PDF with the attack vector using one of the vulnerable method overloads inside their browser. The attacker can thus inject scripts that run in the victims browser context and can extract or modify secrets from this context. The vulnerability has been fixed in jspdf@4.2.1. As a workaround, sanitize user input before passing it to the output method.

CriticalCVSS 9.6Not KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysiscritical

Security readout for executives and security teams

Plain-English summary

Applications using jsPDF before 4.2.1 may let attacker-supplied PDF options place malicious HTML or scripts into a newly opened browser window. If a victim creates and opens the PDF, the script may read or alter sensitive information available in that browser context.

Executive priority

Treat this as an urgent application-security update where jsPDF runs in authenticated browser workflows or handles sensitive information. Identify exposed implementations promptly and upgrade them. The severity is critical, although exploitation requires a specific unsafe data flow and victim interaction, and the supplied evidence does not show active exploitation.

Technical view

CVE-2026-31938 is a CWE-79 HTML injection vulnerability in jsPDF versions earlier than 4.2.1. User-controlled values passed unsanitized through the output function's vulnerable new-window overloads can execute script when the generated PDF is opened. Exploitation requires victim interaction but crosses browser security scope, supporting the supplied CVSS 3.1 score of 9.6.

Likely exposure

Exposure is most likely in browser applications that use jsPDF earlier than 4.2.1, allow users to influence output options, and open generated PDFs through affected new-window paths. Applications that do not pass untrusted data into these options may not be practically exploitable, but their data flow still requires verification.

Exploitation context

An attacker must supply crafted option values that reach a victim's PDF-generation workflow, and the victim must create and open the PDF in a browser. The bundle marks the CVE as absent from KEV and provides no evidence of active exploitation. Public exploit availability is not established by the supplied sources.

Researcher notes

Assessment should focus on call sites using output overloads that open PDFs in a browser context, including wrappers that pass options automatically. Confirm whether attacker-controlled fields can reach the options object without sanitization. The source bundle identifies the fix release and commit, but does not enumerate every vulnerable overload or establish exploitation in the wild.

Mitigation direction

  • Upgrade jsPDF to version 4.2.1 or later.
  • Until upgraded, sanitize all user-controlled values before passing them to the output method.
  • Prevent untrusted users from controlling PDF output options or related new-window parameters.
  • Prioritize browser workflows handling secrets, authenticated sessions, or sensitive generated documents.

Validation and detection

  • Inventory direct and transitive jsPDF versions across source, lockfiles, and deployed browser bundles.
  • Confirm every deployed jsPDF instance resolves to version 4.2.1 or later.
  • Trace whether user-controlled data reaches output options used by PDF-opening paths.
  • Verify application controls sanitize or reject HTML-bearing values before calling the output method.
  • Regression-test PDF creation and opening workflows after upgrading or applying input controls.
Prepared
Confidence
high
Sources
4

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 · medium confidence lookup

CWE-79: User-session and phishing behavior lookup

Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2026-31938 mapping review

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

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Critical
CVSS
9.6 (3.1)
Known Exploited
No
Published

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

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.

2CVSS vectors
5Timeline events
2ADP providers
9Source links

SSVC decision data

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

CVSS vector scores

2 official scores

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
9.6CVSS 3.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L2.86GitHub_M
8.1CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N2.85.2redhat-SADP

Vulnerability scoring details

Base CVSS 3.1 score

9.6Critical
CVSS 3.1 vector shape for CVE-2026-31938Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

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. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. ADP timelineredhat-SADP

    Made public.

  3. CVE publishedCVE Program

    The CVE record was published.

  4. ADP timelineredhat-SADP

    Reported to Red Hat.

  5. CVE updatedCVE Program

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

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc
redhat-SADPjspdf: jsPDF: Cross site scripting via unsanitized output options
other:Red Hat severity ratingcvssV3_1
  • 2026-03-18T04:02:27.320Z: Reported to Red Hat.
  • 2026-03-18T03:05:44.964Z: Made public.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
parallaxjsPDF< 4.2.1Listed
Weakness

CWE details

CWE-79

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

CWE-79 · source CWE mapping

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs