Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c55e41ad5708c6b…

MALICIOUS

PDF

82.6 KB Created: 2021-09-04 21:23:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c543b011cb39f9eddec9012913620d08 SHA-1: ad8d9a49fab8d0defdad0bac92e3fd91c036fce6 SHA-256: 8c55e41ad5708c6bce793769455213f726394bbc9f152d3f488fbff6ace3181f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Several heuristics identified the document as a link farm, with many URLs pointing to potentially compromised CMS upload directories or disposable hosting. While no scripts were directly extracted, the presence of numerous external links suggests an attempt to redirect the user to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://hamzakocakoglu.com/userfiles/file/46523469021.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/005dafe955bda723ad0975c9c15b6593/texukifewobifutix.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/16093e76e258aa---natuwuguluxisuduxibubal.pdf
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/46db294c4a5b5d905d26fdfe10cb5bf8/lotivozavaxanunidebibete.pdf
    • https://ukmalayalamnews.com/userfiles/file/nubodiwa.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16090d23d0a10c---xawibelovelila.pdf
    • https://giustofiori.it/file/gamigovoxew.pdf
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/3v2bul5kklram1kcuccpkimvv1/nidetitere.pdf
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607174179f823---4585383200.pdf
    • https://proektasis.gr/admin/spaw2/uploads/files/61779299523.pdf
    • http://surausa.com/uploads/files/5007044668.pdf
    • https://stayatrosetta.com/wp-content/plugins/super-forms/uploads/php/files/l1rkg08gh8hqgequtl80unk1g3/20846301253.pdf
    • http://agataklimowska.pl/userfiles/file/2938072853.pdf
    • https://orangerun.re/photo/files/42999877381.pdf
    • http://cuuhoatudong.com/upload/files/63255969123.pdf
    • https://cahayamimpi1.com/contents//files/2148534079.pdf
    • http://absolutelyneon.com/userfiles/file/buronotojokonajixuf.pdf
    • http://vitali-schulz-eiskunstlaufen.de/userfiles/files/nuzusolegu.pdf
    • http://ash-graphy.com/userfiles/file/fevukidug.pdf
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/lat89javsfl6udivo0bk8aabck/85095859117.pdf
    • https://vntdc.com/upload/fck/file/sisivobixepugepofifapot.pdf
    • https://parklanehotel.asia/userfiles/file/sawajisunavafilolu.pdf
    • http://geerhannutpourreussir.be/docs/upload/files/kazixijazunisuzubufixirus.pdf
    • http://duocmyphamcongty.com/app/webroot/uploads/files/31611617839.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=caravan+aptitude+test+book+2018+pdf+free+download
    • 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_off0000d369.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD369 16792 bytes
font_01_sfnt_off0000eb7b.bin
dd95b0e23a18fa2110ac5db72d62e88a21f6c8d0001976d90e3c8888cc6441f3
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB7B 20540 bytes
font_02_sfnt_off000120de.bin
1e8cff09dd0440d6aaa643479e30808c0730a3d035e8d1f7bf38f239f97fe8d2
pdf-font-stream PDF embedded font (sfnt) at offset 0x120DE 11508 bytes