Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd0caf11022b1f37…

MALICIOUS

PDF

74.1 KB Created: 2021-06-30 21:06:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1fb5c2d79fbf7ed47d6e15195b7d75e6 SHA-1: 7576f132a49793627f3b749ab1146a890cb5bba8 SHA-256: fd0caf11022b1f37390f339016df04ef61cbb8a139ba07258120ae9426fede1a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of links, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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 https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/676e216250f604e5686179e67c8ff641/40441992045.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/li3ota7pl7vh9ta1l6k4va55b0/rawesugifakelebu.pdf
    • http://bannhuaduong.net/upload/files/lijegonugirenaneb.pdf
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160a52ace93007---lifuxu.pdf
    • http://laros.cz/UserFiles/file/98646952232.pdf
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16073031e750c1---2204672227.pdf
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b17221627b7---51349716106.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160c0b30b68c92---86589041141.pdf
    • http://bwc.lt/i/nafox.pdf
    • https://la-klamm.org/Files/files/80433684265.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160722c2e4fa9d---tukanewujijutadug.pdf
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/k7kqno87rk22a5cc9tvhrbb2p7/18535535651.pdf
    • https://www.treehousecare.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606c961babfda---lugujoxaxorutiwebawomokor.pdf
    • http://skncn.com/u/files/4700335840.pdf
    • http://kaizenlife.com/ckfinder/userfiles/files/88644085498.pdf
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/soeuu7vgjrmrqabk9mhgclo3i2/dawimow.pdf
    • http://trunglam.vn/uploads/userfiles/file/36581612862.pdf
    • https://thediamangroup.com/_images/files/86603295435.pdf
    • https://altonika.pro/files/fck/file/rabusomavorarunazenok.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/bc05f342be209abf52157ef4f2b39511/gavojuzavuzu.pdf
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608c2d0d82541---tanazitawitezinavazavud.pdf
    • https://wulf-sanitaer.de/wp-content/plugins/super-forms/uploads/php/files/lpo75i282rv0til6gg0603e5k9/zazovibosukomipud.pdf
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/d7e811a8c3da268d3a7e5ef1e700a11a/74785524585.pdf
    • http://goldway.jp/upload/board/file/dosorisafidesex.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=top+selling+candy
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c29e.bin
3646d2ff967f5defefe151e4f92d716bc2d0ca2c4b6b223e1c21990439e90b3c
pdf-font-stream PDF embedded font (sfnt) at offset 0xC29E 10568 bytes
font_01_sfnt_off0000daa6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAA6 16792 bytes
font_02_sfnt_off0000f2b8.bin
3a0eeec80cc913bd6cf5220a6bca43d852c9626300fa42af7bf5051874212fda
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2B8 15860 bytes