Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1c3d7f7ababd70e…

MALICIOUS

PDF

83.2 KB Created: 2021-08-31 19:23:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d455ffd255af99238a6d4d365a25b4d5 SHA-1: 9620af528db1991d4c0960df28cea1c6f46a5f9f SHA-256: c1c3d7f7ababd70eb880a899495084d4336c6885e5e236137ae39d531a1c62b4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links pointing to compromised WordPress sites, which in turn redirect to other URLs. This behavior is indicative of a link farm designed to obscure the final malicious destination, likely for phishing or malware delivery. The ML classifier and ClamAV detection strongly support the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 7

  • 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.
  • 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 https://inwebjor.ru/uplcv?utm_term=driving+a+manual+transmission+car
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/d918536871ef7cd90556d13d5f8a2425/85101494925.pdf
    • https://nikosdimos.gr/userfiles/file/94642356294.pdf
    • http://acecaalcoy.com/userfiles/file/vemaruwekefewafaluxafu.pdf
    • http://agrobud.net/uploaded/file/49849077429.pdf
    • http://canadapremiumlubes.com/survey/userfiles/files/38984447416.pdf
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/darupupedifi.pdf
    • http://harnettcountyhba.com/userfiles/file/8605122780.pdf
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/0jeok5plcns94c14ma5563ubo1/fuxefebo.pdf
    • http://zhengfutz.com/v15/Upload/file/2021828746125941.pdf
    • http://hourinkan.net/js/upload/files/94580666740.pdf
    • http://diplomat2014.ru/ckfinder/userfiles/files/vipekijazijozat.pdf
    • https://myupfield.link/wp-content/plugins/super-forms/uploads/php/files/hm705c9ql8l2oalfqda4filp3v/tominomisekuxajadadugoro.pdf
    • https://livnica-metalurg.com/images/pages/file/demegodewawunewaxobuxe.pdf
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/c59ed91df039a37c6a2406477ddd5f5a/66038067937.pdf
    • http://erdbau-rauch.at/98610261810.pdf
    • http://dentish.ru/ckfinder/userfiles/files/22166110297.pdf
    • https://ahl2005.com/ckfinder/userfiles/files/49418172215.pdf
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/01bio87ij2h663p83canftj3j7/39070028919.pdf
    • http://rlponder.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/60234369182.pdf
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/a2cae2e3d48ec77395c0bbdeacb6b31f/xupimesuvevutapurukopa.pdf
    • http://abw10thstreetne.com/uploads/files/87679963931.pdf
    • http://jonkmp.nl/img/cms/file/66246231898.pdf
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/22866922276.pdf
    • http://rocb-ap.org/file_media/file_image/file/buwotojipobazevotidut.pdf
    • http://elcivan.com/admin/UserFiles/file/buxomubavaju.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_off0000e137.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE137 16792 bytes
font_01_sfnt_off0000f94e.bin
3ff02258239eebc3b2b7c96490bc1b48583133375708cfd9c4de8e1801070289
pdf-font-stream PDF embedded font (sfnt) at offset 0xF94E 10608 bytes
font_02_sfnt_off00011191.bin
2997df28daa1dcbbee76cf099701a0e284b044ccdf8b6c150e2c38ed3ca65b44
pdf-font-stream PDF embedded font (sfnt) at offset 0x11191 17184 bytes