Malicious PDF — malware analysis report

Static analysis result for SHA-256 f35af725d382b0b5…

MALICIOUS

PDF

86.5 KB Created: 2021-07-27 20:52:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5c91ccc1f635932393f5a7cb0b3570e8 SHA-1: 5b2ddca0049c8e277bf91767382aa0a57aade4ee SHA-256: f35af725d382b0b57b39d225cad8c9e8e0295f439616acffeb2cdfa88a730419
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a phishing or malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://auto4-spb.ru/public/images/ckfinder/files/75834523235.pdf
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d60a9cc05b---42110775342.pdf
    • http://ustunongel.com/image/files/75066664898.pdf
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/dedcf595a26f7ac81e8b8dfe96187d4b/mamafibaduveliviwazadavu.pdf
    • https://boyanbolyarski.com/userfiles/file/kebabumanazo.pdf
    • http://baraanduliaptti.org/userfiles/file/jelokibe.pdf
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/pdjkkg3fmkh6q9j5sjlcrnls9m/rekuderivixokiso.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a853c7219c9---govebuxel.pdf
    • http://centroolosprato.it/userfiles/files/wolevileda.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7aa3e5dbe---sevudifexawipo.pdf
    • http://begemot-rus.com/uploadfiles/file/2021061701062273499.pdf
    • http://aircond.md/upload_fck/file/10029516588.pdf
    • http://straub-online.ch/userfiles/files/99152947636.pdf
    • https://its-bulgaria.bg/files/file/powonawevevemanidev.pdf
    • https://bd-sokolovska.eu/userfiles/file/66989907415.pdf
    • http://www.toptehnik.si/images/sevanugizuroxogi.pdf
    • https://empresa-venta.hr/files/mixagunusiwaxajofejo.pdf
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/d566b36534c1399b85724b9d119ed8a7/wuvirobubuvuzi.pdf
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/0idi37fvq1fh2g0p45co7af4bn/wekezalegimuboxirakefi.pdf
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/dg1ur2dumrthm4vejibfqdktu3/sozunebemop.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ef8766f67---zifemizapazuno.pdf
    • http://heldermusic.nl/ckfinder/userfiles/files/kuxemu.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c91e78f996---ladofukapaweposagixat.pdf
    • https://classicandcamper.co.uk/wp-content/plugins/super-forms/uploads/php/files/th4ogo452vvm742rmu6d9fkh7t/lubezesamefadusiduje.pdf
    • https://www.perfumista.co.uk/wp-content/plugins/super-forms/uploads/php/files/c2f196c9cffdca1effa17c6db3786211/65138656591.pdf
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/ae1cb8875e3551a66d744b2331051855/jabozudodulalalamasibufi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=digi+002+rack+drivers+windows+7
    • 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_off0000ec9d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC9D 16792 bytes
font_01_sfnt_off000104af.bin
6c1978c9be5bdb14f76fe5f33ffb01f8883932b6c20742427da93425106c69a5
pdf-font-stream PDF embedded font (sfnt) at offset 0x104AF 17104 bytes
font_02_sfnt_off0001314f.bin
26444a8a99eaadd4bc5a11d2d171750cdb15dcd1d0e719b66397b57c50cef9a4
pdf-font-stream PDF embedded font (sfnt) at offset 0x1314F 10936 bytes