Malicious PDF — malware analysis report

Static analysis result for SHA-256 ded86f8b3b4f54e9…

MALICIOUS

PDF

77.1 KB Created: 2021-06-25 19:51:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bf07de9d7e8c3f1492484e66d8bacca0 SHA-1: 3e5991dc0394f6854d649ee026b9a8e7d99d0737 SHA-256: ded86f8b3b4f54e978c03c6e2d98d8631a897ed269598666e635c221f893cd82
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to compromised CMS upload directories. These links likely serve as a distribution mechanism for further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16081bd0be17d2---33606736255.pdf
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/g99fla1r96mm09sclfjknngqjb/jewetitopafiwuwikuwa.pdf
    • https://bestofbucerias.com/upload/file/putadunapib.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074aca653fc8---52422476304.pdf
    • https://genegurumiraclehealer.com/userfiles/file/98227309491.pdf
    • https://dixietemporarystorage.com/wp-content/plugins/super-forms/uploads/php/files/d742c9a0c18a2bbb08cb911c2e145cd2/fomuxipigivu.pdf
    • http://cukierniabrzezinski.pl/www/artizam/fck/file/junegosidegukep.pdf
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160d52bba34b1d---womekideworujebojidepa.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b7ad26085e6---25495057936.pdf
    • https://stopserv.ru/files/file/ledozupunikaj.pdf
    • https://alakharia.com/public_html/userfiles/file/42134852211.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607b9f2367712---nokivakibazimiwif.pdf
    • http://chataphan.com/file_media/file_image/file/lotatuk.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b32a54cce72---23324333175.pdf
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7e0a510a8---xenogumexasejaga.pdf
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/6eb4b4727017a324cdc3b0296cfc0657/sexetufomevuk.pdf
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c8c1d321d4---27971494438.pdf
    • http://cheumst.com/upload/fckeditor/file/58768433646.pdf
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/gtk88agt2ksid1389v0vjqaja2/17022246547.pdf
    • https://aradovan.com/userfiles/file/18250031225.pdf
    • https://areicon.com/images/file/77991997412.pdf
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/pseq2sgs2j6oilsjmu4ibqlha2/25928107905.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=st+george%27s+aggregates
    • 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_off0000ca79.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA79 16792 bytes
font_01_sfnt_off0000e290.bin
9eba27ce9ea5c1bb6792c1fb5b56d58b50293114f99bdb3b81f5e1d6981c402a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE290 10148 bytes
font_02_sfnt_off0000f967.bin
9d87f1819ac85f657f8879476fe0f492a54e74275b228a98186734f6993db1ac
pdf-font-stream PDF embedded font (sfnt) at offset 0xF967 17440 bytes