Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b51b19b571550e0…

MALICIOUS

PDF

85.8 KB Created: 2021-07-30 17:05:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4a267ac80177320ccb41f26636b2f4a8 SHA-1: e04978bf977209bd05452c463a19607d5bc55b5f SHA-256: 5b51b19b571550e04425f36b9fa8ce25adadc3ae952a60dd1d6b3a6566935e05
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised websites and disposable hosting domains, likely for phishing or malware distribution. Although no scripts were extracted, the PDF structure and numerous embedded URLs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://catamma.ru/uplcv?utm_term=les+pronoms+ind%C3%A9finis+exercices+corrig%C3%A9s+pdf PDF link annotation
    • http://nfrostov.ru/upload/files/pipagafak.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/16102ec0f5ebca---11815854525.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/5193b0f9cd0d033eab3d4296c9731af9/vepaxogatixedo.pdfIn PDF document text
    • http://futureinfashion.com/ckfinder/userfiles/files/nabijujupebil.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16098856a1a99a---24515424855.pdfIn PDF document text
    • https://jagamimpi.com/contents//files/deradidogibo.pdfIn PDF document text
    • http://sunarfactory.com/userfiles/files/47537295555.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1609154ec29ad3---zanonew.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e8cfec7a50a---16503520531.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a66bca5b911---vonowesub.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/f272d9a80ac841cbf5a03cc6240f39d8/4934472669.pdfIn PDF document text
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/9702bb000093c6d7c38f2f13594502be/77275838249.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f3d98a7c900---42566860971.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160776803873b2---46924165489.pdfIn PDF document text
    • http://poiskvod.ru/images/file/97031076243.pdfIn PDF document text
    • https://veaodaibrahma.com/uploads/image/files/84853856039.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/12820254430.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/38306662580.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160916a7163c4d---tatakokowaj.pdfIn PDF document text
    • http://www.lnk-creation.fr/upload/file/53267049140.pdfIn PDF document text
    • http://mcutech.net/upload/2021/07/file/16266693011294487059.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/0eos402ijblvtpaar8383tmpf1/94146109083.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8abbf3986a---99638418515.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/q6lkr96n0oob53dqrrsjo8dr24/letogagalagifoj.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/f21olnc3ko3kj7ectcbta91fut/34857849080.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e5da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5DA 10868 bytes
SHA-256: b4b54d859519b94eb995781d4c2956511c031f57b9a26b80e4303d00e0cc38e5
font_01_sfnt_off0000fe6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE6A 19144 bytes
SHA-256: afb3418bbfef21a234734f01edd8a3be0b406e7ce6e1320563351c20b6a3056c
font_02_sfnt_off00012f2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F2C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1