Malicious PDF — malware analysis report

Static analysis result for SHA-256 623fb142cfa1e7d9…

MALICIOUS

PDF

6.8 KB Created: 2008-31-20 53:85:00 Authoring application: Scribus 1.3.3.12 (via Scribus PDF Library 1.3.3.12)
MD5: 82e58f55daf0e1cf91913c6d88c13353 SHA-1: cfdfbc26cfb2cdbea717dfa7ef0ced93138b1ce0 SHA-256: 623fb142cfa1e7d90406e685237715647c2b9e038b4c7269a109f13dabf5d044
650 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains embedded JavaScript that exploits multiple known vulnerabilities in Adobe Reader, including CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The JavaScript is designed to download and execute a second-stage payload from the URL http://gwb-cash.com/cv/load.php?e=2. This indicates a clear intent to compromise the user's system.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 15

  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution.
  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits.
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure.
  • Pidief-style multi-CVE JavaScript dispatcher critical CVE likely PDF_PIDIEF_MULTI_CVE_DISPATCH
    A single JavaScript body branches on app.viewerVersion and invokes two or more of the canonical Reader sinks (Collab.collectEmailInfo, Collab.getIcon, util.printf with a field-width format string). This is the 2009-2010 Pidief.J multi-exploit landing template: a per-version dispatcher that fires the matching CVE chain for whichever Reader version opens the file.
  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • Multi-CVE Adobe Reader JavaScript exploit kit critical PDF_ADOBE_READER_MULTI_CVE_JS_KIT
    One recovered JavaScript stage contains multiple version-gated Adobe Reader exploit branches. This is stronger evidence than independent API keywords: the PDF is selecting old Reader vulnerabilities by viewer version and running heap-sprayed Acrobat JavaScript exploit paths.
  • ClamAV: Pdf.Exploit.CVE_2009_0927-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.CVE_2009_0927-1
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits
  • Generic recovered JavaScript exploit stage high PDF_GENERIC_STAGE_RECOVERY
    Bounded static stage recovery exposed hidden JavaScript through generic transforms such as null-byte collapse, percent decoding, marker replacement, arithmetic character codes, fromCharCode, numeric arrays, numeric-array minus-key decoders, alphabet-index arrays, /Producer half-difference metadata arrays, hex literals, marker-stripped Base64 literals, custom 6-bit XOR table decoders, or repeated-marker hex carriers. This rule is emitted only when the recovered stage contains exploit-like Acrobat JavaScript or shellcode markers.
  • PDF JavaScript shellcode contains an embedded download URL high PDF_JS_SHELLCODE_DOWNLOAD_URL
    Decoded PDF JavaScript shellcode contains a hardcoded http(s) URL stored as little-endian %uXXXX Unicode escapes. Reader exploit shellcode embeds the second-stage fetch URL this way and pulls it down with a urlmon/URLDownloadToFile-style download-and-execute (commodity downloader behaviour rather than a specific Acrobat CVE).
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://gwb-cash.com/cv/load.php?e=2

Extracted artifacts 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0013_001.js
1b912a4c50be2e231e3343507315952ade95e36ed50b6221000cc69edc3eafbe
pdf-javascript-stream PDF /JS object 13 at offset 0x3E0 5339 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
javascript_obj0013_002.js
365ad5a9a55487a2eea454a623cfe02f2474ee3cf39d78e9512db686a6c705cc
pdf-javascript-stream PDF /JS object 13 at offset 0x406 5969 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
generic_stage_recovery_000.js
15e056fabd514d454df7e78b0c7261093416be3a7a6c82fdb6a2c9c01ee7eef0
deobfuscated-js generic stage recovery percent-decode from JavaScript object 13 at offset 0x3E0 5335 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
generic_stage_recovery_001.js
a250cd887f09d720ecfed05d13c9fded976a24eb4e98b903976e3d4e4b89a924
deobfuscated-js generic stage recovery percent-decode from JavaScript object 13 at offset 0x406 5965 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
generic_stage_recovery_002.js
548f7beb2fd9df674cfba87caa4f8e075c7721b96b76b042e9731d8d5a34f7e4
deobfuscated-js generic stage recovery percent-decode from combined JavaScript objects at offset 0x11 11325 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 18 eval/decoder/string-building token(s). Carved artifact contains 2 long base64-like blob(s).
combined_document_js_000.js
14d03728a65999c5fd4b7f091bbfc87f15e015eefce979722c736c423153fc6c
deobfuscated-js combined document JavaScript streams at offset 0x11 11333 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 18 eval/decoder/string-building token(s). Carved artifact contains 2 long base64-like blob(s).