# What is CVE-2026-109619?

> CVE-2026-109619 is a critical-severity flaw (CVSS 9.2) in the software it affects, published on 20 October 2026. It is on the list of flaws known to be exploited, so criminals are already using it. The latest forecast puts its chance of use in the next 30 days at over 99%. If you run an affected version, patch it first.

Canonical page: https://www.edgeprotect.io/what-is/cve-2026-109619

## At a glance

- **Verdict:** Fix this now. Attackers are using this flaw today. If you run an affected version, it goes to the top of your list.
- **EdgeProtect risk score:** 89 out of 100 (Critical); action: Emergency patch. Kept up to date as the evidence changes.
- **Severity:** Critical (CVSS 9.2 out of 10)
- **Known to be exploited:** Yes, it is on the government list of flaws known to be exploited
- **Chance of use in the next 30 days:** over 99% (latest exploit-likelihood forecast)
- **Published:** 20 October 2026
- **Record last updated:** 21 October 2026
- **Affected products:** 0

## What is CVE-2026-109619? In plain terms

Here is what the published record says about this flaw, and what kind of weakness it is.

### The official description

Unauthenticated remote code execution vulnerability in PHP core, the second of two flaws known as "php2shell". This one had not been independently reproduced at the time of writing. The PHP security team rates it critical (CVSS v4.0 9.2) and scheduled an out-of-band security release for 21 October 2026 at 14:00 UTC, which publishes the affected and fixed versions; CERT-EU (Security Advisory 2026-018) warns that all PHP versions from PHP 5 onwards could be affected. Details leaked on 20 October 2026, about 15:20 UTC, ahead of a coordinated disclosure planned for later that week, and the PHP team brought its release forward. There are reports of exploitation in the wild, not yet confirmed by the PHP security team or listed by CISA. There are also reports of a leaked exploit tool called "PHP2Shell" said to work against every release from PHP 5.4.0, and researchers expect mass exploitation soon after the patch is published. The root cause has not been published by PHP. An unverified write-up circulating with a proof-of-concept bundle attributes the php2shell flaws to heap use-after-free bugs in the session extension's upload progress handler (session.upload_progress, php_session_rfc1867_callback) and in the multipart/form-data parser, so any multipart POST to a PHP endpoint may reach the vulnerable code.

## Is CVE-2026-109619 being exploited? Yes

Attackers are already using it. It is on the government list of flaws known to be exploited, and the latest forecast puts the chance of it being used in the next 30 days at over 99%.

Exploit likelihood over the last 7 days: <0.1%, 5.8%, 6.0%, 6.2%, >99%, >99%, >99%.

### Timeline

- 20 October 2026: Published
- 21 October 2026: Record last updated
- 26 October 2026: Exploit likelihood jumped
- 27 October 2026: Added to the known-exploited list

### How EdgeProtect ranks it

CVE-2026-109619 scores **89 out of 100 (Critical)**, with the action "Emergency patch".

Every published flaw gets a risk score from 0 to 100, kept up to date as the evidence changes. Four things go into the score, from the one that counts most to the ones that count less:

- Evidence it is being exploited: biggest factor
- How severe it is: strong factor
- How widely exposed it is: key context
- Real threat activity around it: key context

85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score. When this flaw matches software you track, it lands in your list with its score and the reasons behind it.

## Who is affected by CVE-2026-109619?

No affected products have been listed for this flaw yet.

## How do I fix CVE-2026-109619?

1. **Check whether you run it.** Compare your versions with the affected products above. Not sure what you run? EdgeProtect can work it out from your public website, or you can pick it from a list.
2. **Apply the vendor’s fix.** Install the update named in the vendor’s advisory. We’ve put the advisories and patch notes first in the list.
3. **If you can’t patch today.** Follow any mitigation the vendor publishes, and limit who can reach the affected system from the internet until the update is in.
4. **Check it wasn’t used before you patched.** Because criminals are already using this flaw, look for signs of a break-in on affected systems using the vendor’s guidance.

### References

- [php.net](https://www.php.net/archive/2026.php#2026-10-20-1) (Vendor advisory)
- [php.net](https://www.php.net/supported-versions.php) (Vendor advisory)
- [huntress.com](https://www.huntress.com/blog/php2shell-leaked-critical-php-vulnerabilities) (Third-party advisory, Mitigation)
- [github.com](https://github.com/Neo23x0/process-watcher/blob/main/emerging-threats/php-rce-october-26/README.md) (Mitigation)
- [watchtowr.com](https://watchtowr.com/intelligence/php-cve-2026-109618-faq/) (Third-party advisory)
- [bleepingcomputer.com](https://www.bleepingcomputer.com/news/security/php-warns-admins-of-two-critical-flaws-emergency-patches-coming-tomorrow/) (Press/media coverage)
- [thehackernews.com](https://thehackernews.com/2026/10/php2shell-two-unpatched-critical-php.html) (Press/media coverage)
- [cert.europa.eu](https://cert.europa.eu/publications/security-advisories/2026-018/) (Third-party advisory, Government resource)
- [sansec.io](https://sansec.io/research/php2shell) (Third-party advisory)

## Questions

### What is CVE-2026-109619?

CVE-2026-109619 is a critical-severity flaw in the software it affects, published on 20 October 2026. Here is what the published record says about this flaw, and what kind of weakness it is.

### How serious is CVE-2026-109619?

It scores 9.2 out of 10 on the CVSS severity scale, which is critical. Our risk score for CVE-2026-109619 is 89 out of 100, which is Critical. Its action is "Emergency patch". Attackers are using this flaw today. If you run an affected version, it goes to the top of your list.

### Is CVE-2026-109619 being exploited?

Attackers are already using it. It is on the government list of flaws known to be exploited, and the latest forecast puts the chance of it being used in the next 30 days at over 99%.

### How do I fix CVE-2026-109619?

Install the update the vendor names in its advisory, linked first under "How do I fix" on this page. If you can't patch today, follow the vendor's mitigation and limit who can reach the affected system from the internet. Because criminals are already using it, also check affected systems for signs of a break-in.

## Does CVE-2026-109619 affect you?

EdgeProtect keeps checking for you:

- **Tell us what you run.** Pick your software from a list, or let us work it out from your website.
- **We match it to every flaw.** Over 400,000 published flaws, checked against your list.
- **Ranked by real-world risk.** Every flaw gets a 0 to 100 risk score, kept up to date, led by evidence criminals are using it.
- **Told as soon as we know.** An alert by email, in the app or by webhook to your own tools.

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