Malicious PDF — malware analysis report

Static analysis result for SHA-256 40b2436653feff27…

MALICIOUS

PDF

84.4 KB Created: 2021-07-19 23:02:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8526240cd3dd9a0f9b8e72ba6dd83005 SHA-1: 3c9d870d744d70787a86e87c887dce669bc6e30b SHA-256: 40b2436653feff278f2a6a3fa36e712c882611e9595550edd6f4a6ec7c0f5b51
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and a machine learning classifier. It contains numerous links to external websites, many of which point to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to redirect users. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics indicates a pattern of using algorithmically generated URLs on potentially untrusted domains, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9930

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://statenbracy.com/clients/d/d3/d362857cea7b6c304c7898dd6c6993b3/File/pudenuj.pdf
    • https://vico-immobilien.com/ckfinder/userfiles/files/66971583912.pdf
    • https://pjkconstruction.ca/images/file/2063614935.pdf
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/bc68abc12be54751b6f58097b6afd03f/542201131.pdf
    • https://immo-cjeanpaul.lu/userfiles/files/rowulorosofejididosulifi.pdf
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089c157d779c---fifefix.pdf
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/n5qd33vb82lq0ff0j0dr45h4i0/7408447208.pdf
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16075eccb335c0---nagagodojefuzi.pdf
    • http://dermatologomiguelgallego.com/miguel/fck/file/bafagetazavamifofur.pdf
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/c628ded7d88c3b584f25ba6d764347ea/bokatutesunejaw.pdf
    • http://careerdynamic.com/clients/3/3d/3d9dba0a3645e5854abf1db7654b9c86/File/xazubowavimapaz.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ac666762c97---xazulofeviku.pdf
    • http://klpa.net/userData/board/file/tisumoparavujokono.pdf
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/3qiohc6h1de7irm0n1m5gv081f/16213020636.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/300e688de68ac10a718f9c49572844c8/87434159494.pdf
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/2a8bade6797cbba2ef470c1d7a7c3a95/sovomeluxefoxefudokaj.pdf
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/160925f3ab9d23---16122267144.pdf
    • http://a-kamen.com/userfiles/file/jujotemano.pdf
    • http://brucemaymemorialgolftournament.com/clients/d/d2/d245e0393a5bbb16d67b82808c007790/File/zaxurubumozosaxilok.pdf
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/7ba6a0d7bdc3fff48f5036cd101b54ae/kexugusar.pdf
    • http://udaybharat.in/ckfinder/userfiles/files/94594924895.pdf
    • https://rimsball.com/ckfinder/userfiles/files/75770413820.pdf
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608036177b966---22698703688.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=black+knight+glaive+ds1
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d26e.bin
67fbb0623260c9ef6511f6585c93f67cd4d22bfa04705bba98c9e7e833fe6264
pdf-font-stream PDF embedded font (sfnt) at offset 0xD26E 10692 bytes
font_01_sfnt_off0000eacb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEACB 16792 bytes
font_02_sfnt_off000102dd.bin
3e92c538d6d72a27bc047b1eae886015bab652f3fb544c5a84d3bc6d325739e0
pdf-font-stream PDF embedded font (sfnt) at offset 0x102DD 15816 bytes
font_03_sfnt_off00012ba1.bin
614ba864557de8a86ea14f2c07de0c041d7c79a880fe7236790619f79cdccf51
pdf-font-stream PDF embedded font (sfnt) at offset 0x12BA1 17024 bytes