CVE WatchNov 13, 2026

CVE-2026-128343

exceljs through 4.4.0 contains a denial of service vulnerability that allows attackers to block the event loop by supplying unbounded row r

CVSS

7.5

High

EPSS

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KEV

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Exploit Today

0-100

Published: Nov 13, 2026 · Last modified: Nov 13, 2026 · CWE-606

EPSS · 30d

Not enough EPSS history yet.

Technical description

exceljs through 4.4.0 contains a denial of service vulnerability that allows attackers to block the event loop by supplying unbounded row r attributes parsed in row-xform.js. Attackers can craft an XLSX file with a row numbered far beyond Excel's limit, making getSheetValues(), workbook writes and CSV export consume time proportional to that number.

Official references

Related CVEs

CVECVSSEPSSKEVRExploitTitleMod.

CVE-2026-1283427.5 HIG

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——0ExcelJS through 4.4.0 contains a denial of service vulnerability that allows attackers to block the event loop by supplying an unbounded sheetId in xl/workbook.xml. Attackers can provide a workbook with a huge sheetId, making the sparse worksheet array walk stall worksheets, getWorksheet and writeBuffer for seconds.10h CVE-2026-1252645.5 MED

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——2FFmpeg through 9.0.2 contains an uncontrolled resource consumption vulnerability in parse_frame_header() in libavcodec/jpegxl_parser.c that fails to validate TOC entry counts against remaining input. Attackers can supply a crafted JPEG XL frame header with a permuted TOC and huge toc_count, making the parser loop excessively and exhaust CPU.3d CVE-2026-1180377.5 HIG

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——6In Progress® Telerik® Document Processing Libraries prior to version 2026.3.1027, uncontrolled recursion, infinite loop, unchecked loop condition and inefficient regular expression vulnerabilities in RadSpreadProcessing and RadSpreadStreamProcessing allow an unauthenticated attacker to terminate or hang the host process via a crafted XLSX or XLS workbook or formula.1d CVE-2026-1075697.5 HIG

31.6%

——9Unchecked input for a loop condition in Progressive Robot hMailServer 6.0.0 through 6.3.6 allows a remote unauthenticated attacker to stop the server carrying mail. The server bounds the mail it generates in response to a message - a rule forward, reply or copy, an account forward, a Sieve redirect, vacation or notify, a bounce, an out-of-office reply - by a counter it carries in the message's X-hMailServer-LoopCount header, and makes no more once the counter reaches the configured rule loop limit (5 by default); that is what ends a forwarding or auto-reply cycle in a bounded number of hops. X-hMailServer-LoopCount is an ordinary header that is not stripped from mail arriving from outside, and the server read it with a signed conversion and no validation, so a count below zero passed every test against the limit: a sender who sets X-hMailServer-LoopCount to a negative value, or on the Linux builds to a value above the 32-bit signed range that the conversion wraps to a negative one, lifts the bound, and a message that enters a generated-mail cycle then loops up to about two thousand million times, each hop a queued message and a delivery, filling the queue and disk and stopping mail service. The Sieve notify action (from 6.2.22) consulted no limit at all, and its increment of the count could overflow a signed integer; and an account could reset the counter on its own mail through a Sieve editheader of the header (from 6.2.22) or a rule Set header value action (all versions) ahead of a forward or redirect.24d CVE-2026-953944.7 MED

3.4%

——1Microsoft Network Monitor file parser large loop in 4.6.0 to 4.6.8 and 4.4.0 to 4.4.18 allows denial of service37d CVE-2026-16652—

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——12Temporal Server did not bound the work performed while searching for a Schedule's next action time. An authenticated caller with namespace write permission could create or update a Schedule that combines a fine-grained cadence with an exclusion calendar that rejects every candidate time, causing the server to evaluate excluded candidates without a per-search work budget. This can consume excessive CPU in Frontend and Schedule worker components. A persisted specification can also cause its backing Schedule Workflow to repeatedly fail and retry, allowing CPU consumption to continue without additional requests until the Schedule is deleted or its backing Workflow is terminated. Repeated or parallel exploitation can deny service. The issue affects availability only; it does not expose or modify Workflow data.52d