Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce37ff18ee058a38…

MALICIOUS

PDF

87.1 KB Created: 2021-06-25 14:52:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7eab603b585ee1bdb099829be4bea05a SHA-1: 78bb8ad44767291dc6626a3a7851d493caa38861 SHA-256: ce37ff18ee058a38456f9dedc907420c052d0d2edb43f043e7aaaf427c30c316
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress sites, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the presence of numerous external links and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly indicate the document's purpose is to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/4ljogdae972i2onur85km2dbeb/49676421573.pdf
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/n8f3kvd0m156j4vvs65q8ehpak/41686391734.pdf
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606ff2aabf0fc---padavevav.pdf
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16087bb8bf23f6---29816591425.pdf
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607048985930c---78031857764.pdf
    • http://xboxheerlen.nl/userfiles/file/68809136502.pdf
    • http://densayhongngoai.com/uploads/userfiles/file/zosobanozesodibuzosoxit.pdf
    • http://allaboutdowney.com/userimages/20792550284.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c77e2dd0809---pidipizunimufesus.pdf
    • https://mymango.ru/wp-content/plugins/super-forms/uploads/php/files/cd6928a9ca2b91968c6f84ed045d8694/wutisewudevovewotidok.pdf
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160bc7a3145e61---87064217292.pdf
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160aa81c595dd9---jexab.pdf
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/97bdef3491af81447b3b77bfd41938dd/wosunujegusufipo.pdf
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b77cce8458f---dubobulop.pdf
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b9a610178df---saxurowoxabifopex.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=word+of+mouth+influence
    • 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_off0000f04c.bin
87f41eca53b5ef37aa8d1e59c70e59edcfd8e80b9288679dc5647810e09d08f1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF04C 18028 bytes
font_01_sfnt_off00012000.bin
a0d59d96e630767af6f9b45812efbfc08d41dcd30aafc15d95e61730460a509f
pdf-font-stream PDF embedded font (sfnt) at offset 0x12000 10504 bytes
font_02_sfnt_off000137ac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x137AC 16792 bytes