Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4788611b541c992…

MALICIOUS

PDF

96.7 KB Created: 2021-07-30 11:41:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dbc8272e91e602279932d4c852a52adc SHA-1: b0cb8d84287b91c72d85ce0bd7e09adba670ee70 SHA-256: a4788611b541c992ceab53d9efdf96d34227bba74ea6d7ce1c65049f06af8c77
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution campaign. The ClamAV detection and ML classifier strongly indicate malicious intent, classifying it as a phishing trojan. The document body is unreadable, but the heuristic findings are sufficient to determine its likely purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://medvor.ru/uplcv?utm_term=lg+g7+thinq+specs+and+features
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/1dcd89d57f780b163d9af1e1c13656d2/90440818770.pdf
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b818360ba10---67869621733.pdf
    • https://lasvegasrebath.com/wp-content/plugins/super-forms/uploads/php/files/ec73ee9e4b60958f34e88ad1af7eb009/sabakosesirififisuvefoz.pdf
    • http://svaz-podnikani.cz/files/file/zozox.pdf
    • https://dacinsara.ro/fckfiles/file/fakakofedutijoxuzisu.pdf
    • http://klubalfa.org/img/userfiles/file/97657691119.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847d3980ce4---34947962201.pdf
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160c8db5fbaeb9---78860769124.pdf
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e9f2b0eef23a321689911c2498767292/6305681454.pdf
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/e0f5ae1061e64582528065448f2888df/pubogibusiraralop.pdf
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/5eb0d4424d544d1d12c91601ceb4d8f5/tisasewunenawop.pdf
    • http://taeguektour.com/FileData/ckfinder/files/20210712_2051F64803AE9195.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b00aeb45d78---dibujarukexokepigef.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160eff56b1f20c.pdf
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16076bb849345a---40888936466.pdf
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/462290be65d91a770957804d81f65d7c/zuzeduluxogoxaxazekijela.pdf
    • https://xn----8sbcehyodmtf1czh.xn--p1ai/userfiles/file/perezide.pdf
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16092df16beba3---senalad.pdf
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/531da1c70e5fbdd5bc2338883b35e478/60499723665.pdf
    • https://podereilmontaleo.it/writable/public/userfiles/file/54686797495.pdf
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/emlq205ktvjmi77emjco6dhac7/12211547664.pdf
    • http://hit-air.pro/ckfinder/userfiles/files/74443085888.pdf
    • 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_off0001131f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1131F 16792 bytes
font_01_sfnt_off00012b31.bin
3ed9e3b3c368a228ac024e0bb09a04a39b5e28df7d7480fe381852adbaff3361
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B31 17868 bytes
font_02_sfnt_off00015a7a.bin
e4558252651b5d4d3b2eabf08283895fbcda894e882ae67dfb20b7ac65267d19
pdf-font-stream PDF embedded font (sfnt) at offset 0x15A7A 10984 bytes