CRITICAL
The isMail transport in PHPMailer before 5.2.20 might allow remote attackers to pass extra parameters to the mail command and consequently execute arbitrary code by leveraging improper interaction between the escapeshellarg function and internal escaping performed in the mail function in PHP
Published Dec 30, 2016
9.8
CRITICALCVSS 3.1
EPSS 97.74%
Description
The isMail transport in PHPMailer before 5.2.20 might allow remote attackers to pass extra parameters to the mail command and consequently execute arbitrary code by leveraging improper interaction between the escapeshellarg function and internal escaping performed in the mail function in PHP. NOTE: this vulnerability exists because of an incorrect fix for CVE-2016-10033.
Affected products
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
9.8 CRITICAL NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact High
Integrity Impact High
Availability Impact High
No CVSS v3.0 score for this CVE.
7.5 HIGH NVD
AV:N/AC:L/Au:N/C:P/I:P/A:P
Access Vector Network
Access Complexity Low
Authentication None
Confidentiality Impact Partial
Integrity Impact Partial
Availability Impact Partial
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
97.74% 0.97738
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
EPSS probability 0.97738
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (10 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 97.74% (0.97738) | 99.90th | v5 (v2026.06.15) |
| Jun 15, 2026 | 98.04% (0.98038) | 99.90th | v5 (v2026.06.15) |
| Mar 17, 2025 | 93.79% (0.93791) | 99.86th | v4 (v2025.03.14) |
| Dec 17, 2024 | 89.18% (0.89178) | 98.98th | v3 (v2023.03.01) |
| Dec 12, 2024 | 96.73% (0.96725) | 99.72th | v3 (v2023.03.01) |
| Aug 3, 2023 | 96.69% (0.96686) | 99.47th | v3 (v2023.03.01) |
| May 17, 2023 | 96.72% (0.96719) | 99.44th | v3 (v2023.03.01) |
| Mar 7, 2023 | 96.76% (0.96758) | 99.39th | v3 (v2023.03.01) |
| Mar 6, 2023 | 84.55% (0.84546) | 99.64th | v2 (v2022.01.01) |
| Feb 4, 2022 | 84.55% (0.84546) | 99.57th | v2 (v2022.01.01) |
Weaknesses (1)
References (19)
- http://openwall.com/lists/oss-security/2016/12/28/1 mailing-listx_refsource_MLISTMailing ListPatch
- http://packetstormsecurity.com/files/140286/PHPMailer-Remote-Code-Execution.html x_refsource_MISCExploitThird Party AdvisoryVDB Entry
- http://packetstormsecurity.com/files/140350/PHPMailer-Sendmail-Argument-Injection.html x_refsource_MISCExploitThird Party AdvisoryVDB Entry
- http://seclists.org/fulldisclosure/2016/Dec/81 mailing-listx_refsource_FULLDISCMailing ListPatchThird Party Advisory
- http://www.rapid7.com/db/modules/exploit/multi/http/phpmailer_arg_injection x_refsource_MISCExploitThird Party Advisory
- http://www.securityfocus.com/archive/1/539967/100/0/threaded mailing-listx_refsource_BUGTRAQThird Party AdvisoryVDB Entry
- http://www.securityfocus.com/bid/95130 vdb-entryx_refsource_BIDExploitThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1037533 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- https://developer.joomla.org/security-centre/668-20161205-phpmailer-security-advisory.html x_refsource_CONFIRMThird Party Advisory
- https://github.com/FriendsOfPHP/security-advisories/blob/master/phpmailer/phpmailer/CVE-2016-10045.yaml
- https://github.com/PHPMailer/PHPMailer/releases/tag/v5.2.20 x_refsource_CONFIRMPatchVendor Advisory
- https://github.com/PHPMailer/PHPMailer/security/advisories/GHSA-4pc3-96mx-wwc8
- https://github.com/PHPMailer/PHPMailer/wiki/About-the-CVE-2016-10033-and-CVE-2016-10045-vulnerabilities x_refsource_CONFIRMPatchVendor Advisory
- https://github.com/advisories/GHSA-4pc3-96mx-wwc8 Advisory
- https://legalhackers.com/advisories/PHPMailer-Exploit-Remote-Code-Exec-CVE-2016-10045-Vuln-Patch-Bypass.html x_refsource_MISCExploitPatchThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2016-10045
- https://www.exploit-db.com/exploits/40969 exploitx_refsource_EXPLOIT-DBThird Party AdvisoryVDB Entry
- https://www.exploit-db.com/exploits/40986 exploitx_refsource_EXPLOIT-DBThird Party AdvisoryVDB Entry
- https://www.exploit-db.com/exploits/42221 exploitx_refsource_EXPLOIT-DBThird Party AdvisoryVDB Entry
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner mitre
Published Dec 30, 2016
Updated Aug 6, 2024
Reserved Dec 26, 2016
Link CVE-2016-10045
CISA Vulnrichment
GHSA-4PC3-96MX-WWC8 Updated n/a