DaystoPatch

CitrixExploited incident

NetScaler ADC and Gateway memory overflow (Gateway/AAA) later exploited for RCE

CVE-2026-8452, CVE-2026-8451, CVE-2026-8655, CVE-2026-10816, CVE-2026-10817, CVE-2026-13474High, CVSS 8.8In CISA's Known Exploited Vulnerabilities catalog since 26 Aug 2026

  • Exploited after a fix existed
FixedFixed for every supported version on the day it became public.

Response

Silence
0h
First public report to first vendor statement
Exposure
same day
First public report to first fix
Follow-through
same day
First public report to a fix for every supported version
  • Vendor silent
  • Vendor statement, no fix
  • Fixed for some versions
  • Fixed when disclosed
  • Date only, no time of day

Timeline and evidence

Open a moment to see its source and archived quote.

  1. First public report

    CVE record CVE-2026-8452 (CNA: NetScaler)CuratedQuote verified

    "datePublished":"2026-06-30T12:41:07.622Z"

    Coordinated disclosure with fixes. watchTowr published a proof of concept on 2026-08-14 and exploitation followed (KEV 2026-08-26).

    Recorded time
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    Curated. Found by a researcher, with a verbatim quote and link.
    Quote check
    Found in the archived copy
    Snapshot
    sha256:625cdad84357b6fe…
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    Yes
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    7 more sources for this moment
    Citrix advisory CTX696604ClaimedQuote verified30 Jun 2026

    NetScaler ADC and NetScaler Gateway Security Bulletin for CVE-2026-8451, CVE-2026-8452, CVE-2026-8655, CVE-2026-10816, CVE-2026-10817, and CVE-2026-13474

    The vendor's own disclosure.

    Source
    Citrix advisory CTX696604 vendor advisory
    Recorded time
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    Claimed. The date the source gives.
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    Found in the archived copy
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    sha256:e9ddbb503b5cc759…
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    CVE.org record CVE-2026-8452ClaimedQuote verified30 Jun 2026, 12:41 UTC

    Memory overflow vulnerability NetScaler ADC and NetScaler Gateway leading to unpredictable or erroneous behavior and Denial of Service if the appliance is configured as a Gateway (SSL VPN, ICA

    CVE record published.

    Recorded time
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    To the minute
    Origin
    Claimed. The date the source gives.
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    Found in the archived copy
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    sha256:625cdad84357b6fe…
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    No, kept for the record
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    Bluesky postClaimedQuote not checked yet30 Jun 2026, 13:54 UTC

    CVE-2026-8452 - Memory overflow vulnerability leading to unpredictable or erroneous behavior and Denial of Service

    Earliest third-party post we hold.

    Source
    Bluesky post social
    Recorded time
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    To the minute
    Origin
    Claimed. The date the source gives.
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    Not checked yet
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    No archived snapshot
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    Research: watchtowrClaimedQuote verified30 Jun 2026, 19:35 UTC

    CitrixBleed To Infinity And Beyond (Citrix NetScaler Pre-Auth Memory Overread CVE-2026-8451)

    Earliest mention we hold (a vetted outlet).

    Source
    Research: watchtowr research
    Recorded time
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    Claimed. The date the source gives.
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    Found in the archived copy
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    sha256:0d89ad0e6238f050…
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    No, kept for the record
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    Mastodon postClaimedQuote not checked yet1 Jul 2026, 05:42 UTC

    Citrix Fixes Flaws in NetScaler Software Exposing Users to File Reads and DoS Attacks Citrix has patched six high-risk vulnerabilities in its NetScaler software, including flaws that could expose

    Earliest third-party post we hold.

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    Mastodon post social
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    Claimed. The date the source gives.
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    Not checked yet
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    No archived snapshot
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    Hacker NewsClaimedQuote not checked yet14 Aug 2026, 08:10 UTC

    You're Back in the Room (Citrix NetScaler Pre-Auth RCE CVE-2026-8452(?))

    Earliest third-party post we hold.

    Source
    Hacker News hn
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    Claimed. The date the source gives.
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    Not checked yet
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    No archived snapshot
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    CISA KEV (CVE-2026-8452)ClaimedQuote verified26 Aug 2026

    Citrix NetScaler ADC and NetScaler Gateway Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability

    Added to CISA's KEV catalog on 2026-08-26.

    Recorded time
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    Claimed. The date the source gives.
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    Found in the archived copy
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    sha256:ef8fffede5c47200…
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    No, kept for the record
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  2. Vendor statement

    at disclosure

    CVE record CVE-2026-8452 (CNA: NetScaler)CuratedQuote verified

    "datePublished":"2026-06-30T12:41:07.622Z"

    Recorded time
    Precision
    To the minute
    Origin
    Curated. Found by a researcher, with a verbatim quote and link.
    Quote check
    Found in the archived copy
    Snapshot
    sha256:625cdad84357b6fe…
    Used in metrics
    Yes
    Dispute this timestamp
    2 more sources for this moment
    Citrix advisory CTX696604ClaimedQuote verified30 Jun 2026

    NetScaler ADC and NetScaler Gateway Security Bulletin for CVE-2026-8451, CVE-2026-8452, CVE-2026-8655, CVE-2026-10816, CVE-2026-10817, and CVE-2026-13474

    Source
    Citrix advisory CTX696604 vendor advisory
    Recorded time
    Precision
    Date only (no time of day is shown)
    Origin
    Claimed. The date the source gives.
    Quote check
    Found in the archived copy
    Snapshot
    sha256:e9ddbb503b5cc759…
    Used in metrics
    No, kept for the record
    Dispute this timestamp
    Citrix bulletin CTX696604CuratedQuote verified30 Jun 2026

    2026-06-30 Initial Publication

    Source
    Citrix bulletin CTX696604 vendor advisory
    Recorded time
    Precision
    Date only (no time of day is shown)
    Origin
    Curated. Found by a researcher, with a verbatim quote and link.
    Quote check
    Found in the archived copy
    Snapshot
    sha256:e9ddbb503b5cc759…
    Used in metrics
    No, kept for the record
    Dispute this timestamp

  3. First workaround

    No official mitigation found yet.

  4. First fix

    date onlysame day

    Citrix bulletin CTX696604CuratedQuote verified

    NetScaler ADC and NetScaler Gateway 14.1-72.61 and later releases

    Fixed builds listed in the bulletin; later changelog entries (2026-07-01 blog link, 2026-07-20 HTTP/2 note) do not change fixed versions.

    Source
    Citrix bulletin CTX696604 vendor advisory
    Recorded time
    Precision
    Date only (no time of day is shown)
    Origin
    Curated. Found by a researcher, with a verbatim quote and link.
    Quote check
    Found in the archived copy
    Snapshot
    sha256:e9ddbb503b5cc759…
    Used in metrics
    Yes
    Dispute this timestamp

  5. Fixed for all versions

    date onlysame day

    Citrix bulletin CTX696604CuratedQuote verified

    NetScaler ADC 13.1-FIPS and 13.1-NDcPP 13.1.37.272 and later releases of 13.1-FIPS and 13.1-NDcPP

    All four supported branches (14.1, 13.1, 14.1-FIPS, 13.1-FIPS/NDcPP) had fixes in the bulletin.

    Source
    Citrix bulletin CTX696604 vendor advisory
    Recorded time
    Precision
    Date only (no time of day is shown)
    Origin
    Curated. Found by a researcher, with a verbatim quote and link.
    Quote check
    Found in the archived copy
    Snapshot
    sha256:e9ddbb503b5cc759…
    Used in metrics
    Yes
    Dispute this timestamp

Send this to your boss

No brief for this incident yet. We write one for every open incident and every critical bug exploited before a fix.

Affected products

  • NetScaler ADC
  • NetScaler Gateway
  • NetScaler ADC FIPS and NDcPP
How we built this timeline

Bulletin CTX696604 fixes six CVEs; only CVE-2026-8452 is in KEV. Citrix described it as a memory overflow leading to DoS; watchTowr's PoC (14 Aug 2026, per secondary sources) showed a heap overflow reachable via malformed SAML messages, and Previdian/Defused reported attacks dropping web shells (Help Net Security, SecurityWeek, BleepingComputer, late August 2026).

The bulletin fetched 22 Oct 2026 still contains no exploitation statement. Fixes predate exploitation, so exploited before a fix is false.

The bulletin's own changelog date ('30 Jun 2026', no time zone shown) matches the CVE record's 12:41Z publication. The Wayback Machine was offline during research, so the initial bulletin text could not be compared, but the changelog shows no fixed-version change.

Related

Citrix report card