Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf974367c1bcad0b…

MALICIOUS

PDF

83.1 KB Created: 2021-09-02 23:00:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aa879b50649747ab6e7d12eb8125edf6 SHA-1: 8b80fd980b28945be0ce8ca213b91c99a47e4250 SHA-256: cf974367c1bcad0b5efe3e7105542f3de3f498a8d88cf59fd91719c4a3f9ebfd
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites acting as a link farm. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classification strongly indicated maliciousness. The embedded JavaScript and link farm structure suggest an attempt to redirect users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6b65344f37---40669777693.pdf
    • http://pujcovnanaradi-tvarozna.cz/userfiles/files/somijon.pdf
    • https://airshow-bg.com/file/rezifufofowinebo.pdf
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612b6a96c1726---jevev.pdf
    • https://vieclamxaydung24h.com/upload/files/41794535588.pdf
    • http://refpecsbelvaros.hu/kepek/files/48549946342.pdf
    • http://fbrasil.com/userfiles/file///gomitoborusagafaduwib.pdf
    • https://cengilli.com/icerik_images/file/gejujikamolerimota.pdf
    • https://aawyx.com/sites/default/imageuser/file/wopeloxesasuxo.pdf
    • http://ncfc.com.tr/ckfinder/userfiles/files/16835270122.pdf
    • http://klubbelgickychobrov.sk/editor_uploads/files/8377434694.pdf
    • https://yptea.com/data/fckeditor/files/6142666348.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074951dbed86---luninotezezinin.pdf
    • http://oasis-inwaste.asia/files/file/nasaluje.pdf
    • http://tovicetour.com/FileData/ckfinder/files/20210811_2900500CC02D55DD.pdf
    • http://pomodorolennep.de/gfx/userfiles/files/98607109203.pdf
    • https://www.basur-tedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160705248d535c---susobanurisaxofig.pdf
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/428b9d47789d1dfce53158df96b846ae/xofamoras.pdf
    • http://www.provinces.cmcgeneralate.org/files/js/ckfinder/userfiles/files/69872207601.pdf
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a0617ab91e8---zovawuwuxatisewi.pdf
    • https://anthonygillant.com/userfiles/file/41956114691.pdf
    • https://a2designbg.com/userfiles/file/tulapifabego.pdf
    • http://bendhigh1970.com/clients/1/10/106e6567aa8bd3cecf4080670b11bd10/File/63148016111.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=types+of+figure+of+speech+in+literature+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_off0000de26.bin
a6f235b0457696de360503456ee85d53a0a59ba70b27fed618d4a5763a2a1f0b
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE26 11076 bytes
font_01_sfnt_off0000f7c4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C4 16792 bytes
font_02_sfnt_off00010fd6.bin
4096da35ef006f0bc5918e3c2f9decd54b6b737c6836e364613363da4b6618e2
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FD6 18064 bytes