Malicious PDF — malware analysis report

Static analysis result for SHA-256 431c1084c6baf0a6…

MALICIOUS

PDF

137.5 KB Created: 2021-06-25 16:11:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e17b0947fb4003666d8d7716c264de6d SHA-1: 243d4d29397ccfb4264612ec71bec253fb1f2091 SHA-256: 431c1084c6baf0a6f1f6406c59d16ac06ae50661bc590fcc25a84e89a5770922
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to direct users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://samavetpharm.com/userfiles/files/mababoz.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/6f8575fbb976cd8affe1bd3ac153c7e2/92031147572.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094826645ecb---36935924756.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/7mkrb5rj5rm74lpa9ces7ss822/46979690812.pdf
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606d50d36d4e4---67982374629.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c4c9770173c---55390474892.pdf
    • https://marjoyunlar.com/calisma2/files/uploads/putiwafulejazakine.pdf
    • http://wchs65.org/clients/b/bb/bb65574a37642f7fe3135935df861e67/File/kadudesevukabosafalevolut.pdf
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/2fjdf7qq50jo9khjr2p2n664ik/97822375568.pdf
    • http://grafichesirio.com/userfiles/files/fapibagasikerudopiweseres.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1609f7512cc55f---5234378333.pdf
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/6js4guvnt4iddq49rpcopocvo6/sumenezewumopejugivigu.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160766d17432a8---jedebozapomeva.pdf
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0404261d28---vuvotogixafumilib.pdf
    • http://slenderclub.cz/ckfinder/userfiles/files/47763899734.pdf
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/gs7jhrfu6ue1sgv2ehi1pitbm6/sivigu.pdf
    • https://ckmusicdesign.nluserfiles/file/kexipafej.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=by127+diode+datasheet
    • 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_off0001b422.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B422 16792 bytes
font_01_sfnt_off0001cc39.bin
9008fff5d7b5032011ec37a915223c2d16fb3c8ab16b9e0d523c60b3d5934ebc
pdf-font-stream PDF embedded font (sfnt) at offset 0x1CC39 10484 bytes
font_02_sfnt_off0001e466.bin
6b4b96257a056589f02d2e8d95d54a0a27ab92793654d58d3dd7d65f4e9b8c18
pdf-font-stream PDF embedded font (sfnt) at offset 0x1E466 20108 bytes