Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4809a10d4796426…

MALICIOUS

PDF

84.1 KB Created: 2021-07-09 05:56:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2006cf0a468463ade721e6ab11aba6cf SHA-1: 78d5ecacaf9a965cb2addfd3864b219ab8e72bf4 SHA-256: c4809a10d4796426de9dbe9610c683b675903deb0d53b7f7c72a3945b1db4479
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised CMS upload directories, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of malicious activity, likely leveraging embedded JavaScript for redirection or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://inifd.london/uploads/file/fapozusoses.pdf
    • http://biomisszio.hu/tmp/rirekaxujibofiga.pdf
    • https://fishboat.hr/files/vedopajelunomoxamate.pdf
    • http://nguyenquangcomputer.com/upload/ck/files/janiliguvudimaxudi.pdf
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071986595ab5---48243800151.pdf
    • http://geo-equipe.it/userfiles/files/povepudumijibip.pdf
    • http://thevelascofamily.com/clients/11614/File/60983030252.pdf
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7461a0b213c7621f8224d71e7b1ce843/wevufobofirezolozomugavo.pdf
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16094888a77ba5---lusino.pdf
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607788ccd48c3---84378673281.pdf
    • http://cmcthailand.com/ckfinder/userfiles/files/labejaxijowatow.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b32ce196656---38278864069.pdf
    • http://etasystem.net./userfiles/files/64618896936.pdf
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/0579391426020a3e65df2942c796eacf/98677602242.pdf
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/6d565856f790e337cda9bc50fc0f1c8d/98686275322.pdf
    • http://gagutp.com/sa_upload/userfiles/file/20210527214155.pdf
    • http://aep-tc.com/cache/fck_files/file/vulekogugelavelugad.pdf
    • http://www.hmh.sk/files/articles/file/11188849383.pdf
    • http://malifer.hu/upload/file/70635341652.pdf
    • http://eastcoastbiker.de/sites/default/files/file/ropimuvasav.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607955e4e9e24---ziligudeme.pdf
    • http://permianhighschool1970.com/clients/e/ef/efee9fcbc667252fc4b649c8163d3733/File/tudapinurukulosokanev.pdf
    • http://residencecarlofelice.com/userfiles/files/667667368.pdf
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/16082a4b825a54---41962757172.pdf
    • http://inwallendorf.de/userfiles/file/febinemisitezomalutudebuk.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=nyc+green+light+law
    • 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_off0000e83d.bin
4c292d4efb2d010a04383a8139acf58df9b7237a2c3d2dca871d1a0f7ec58116
pdf-font-stream PDF embedded font (sfnt) at offset 0xE83D 10396 bytes
font_01_sfnt_off0000ffb7.bin
240465b73d34c6ea2fff2a10de8e0cc4f4a88ccac37d0630ff7c6d8314b6c2b5
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFB7 16676 bytes
font_02_sfnt_off00012b4e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B4E 16792 bytes