Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8bff6cbe7404450…

MALICIOUS

PDF

76.9 KB Created: 2021-09-08 03:33:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4d8e7c9523819fe6a82bb9ee6459a990 SHA-1: beaa30af6cf933883eda3e97396006f9ecb0b25a SHA-256: c8bff6cbe7404450c1f7800c498cb86b834062e413aa2d538d283098c3a0b0a1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on potentially compromised CMS uploads. The embedded URLs suggest an attempt to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://cdmatik.com/uploads/file/lenezedafezitela.pdf
    • https://ekoelprom.pl/public/images/editor/file/44446893904.pdf
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/e03bc53aceb2845b6d3204051c712cfb/zitumag.pdf
    • https://coevent.ru/upload/files/gufowutufu.pdf
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16125408c969e0---10751663581.pdf
    • https://used-machinetools.ro/app/webroot/files/userfiles/files/89771432762.pdf
    • http://sro52.ru/uploads/files/24730510298.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/54b07c7b28a6ac39021e3c871db55db8/37267093189.pdf
    • http://polipadel.com/userfiles/file/vekupulowexokamo.pdf
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/28e84982a99ddfc97c435c75f5a01a0a/pukinepofekelunexoraw.pdf
    • https://cottingham-group.com/cufiles/files/bazowaxab.pdf
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/gekjjj7b4b5a1f0kcebmbk112o/tizebiravofotugejaremiruv.pdf
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160ce7f4196fee---wenupinevafuto.pdf
    • http://domplus.su/userfiles/files/sivipuvuku.pdf
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/tevudivitiboxixapa.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c87fbd5c18---32682289539.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/thi1preph1rq8lkmh1eiuv67ep/libawiwawamigomabusegamik.pdf
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/99eec69353ab4883bc995347652e66b4/42368593894.pdf
    • http://simkoongschool.com/uploads/editer/files/numajated.pdf
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ad2654e3f76---xawipi.pdf
    • http://absigorta.com/E/file/53868156550.pdf
    • https://swift-tw.com/lcc/upload/files/jupifur.pdf
    • http://krakowska98.com/zdjecia/fck/file/memizidobiluverejilimeg.pdf
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608a0145eff02---legijupoda.pdf
    • http://519pf.com/userfiles/files/jusakomowefavo.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=hsc+part+1+pre+engineering+result+2019+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_off0000c5bc.bin
9d7f061567c13502b0468b7257f61fdd90659efe6c23cd48b7f9021422f70204
pdf-font-stream PDF embedded font (sfnt) at offset 0xC5BC 17528 bytes
font_01_sfnt_off0000f2fa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2FA 16792 bytes
font_02_sfnt_off00010b11.bin
ebf9a1691e0cb6381f114ddeb45bbce10a31503d2ec249e4231968e5ce6a9da6
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B11 11228 bytes