Malicious PDF — malware analysis report

Static analysis result for SHA-256 821c6f6885cf6082…

MALICIOUS

PDF

80.1 KB Created: 2021-08-27 04:00:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 15f261ecd08cc241487ba467cfdbede8 SHA-1: d867f7f76b8a2fc8a122d9c84bfe5fb8fa98a35b SHA-256: 821c6f6885cf608256edabd222d151f064e3c14aaaa35198fd6a46b20303b4f0
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised WordPress upload directories or other disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or malware. The presence of numerous links on potentially compromised or disposable domains suggests a link farm designed for obfuscation and evasion.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://sun-green.nl/ckfinder/userfiles/files/gijukamed.pdf In PDF document text
    • https://maggievanostrand.com/uploads/media/file/bugujegeretadubanedoge.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/q54f0p27r4l2m9gkdgqs8r8re0/31922845111.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/crm3etmb7lvkm52c9nku47ivpo/sadakemiviwiwurukep.pdfIn PDF document text
    • http://happy-land.hu/editor_up/dizobuxikinixoratozetigu.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607851363bec0---zazapuviwaxigebudanok.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/b671819a296bb20da74581e1c26ec6b1/26418555732.pdfIn PDF document text
    • https://fotojursa.cz/userfiles/file/zasonejusokuzinegibame.pdfIn PDF document text
    • https://inifd.london/uploads/file/lujenuf.pdfIn PDF document text
    • http://chronicles.ae/userfiles/files/62724974753.pdfIn PDF document text
    • https://www.aserspa.net/wp-content/plugins/super-forms/uploads/php/files/uf74bc4osraj4ne9eirqeijv2t/vavewipidon.pdfIn PDF document text
    • http://arohitourandtravels.com/userfiles/file/javegap.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/nonorutulopoworetab.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c4092c8bbb10dd39749b4e32cc220ce6/84281851422.pdfIn PDF document text
    • http://jhdljz.com/userfiles/file/1626588545.pdfIn PDF document text
    • https://metricgroup.it/uploads/file/81116046419.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/160bba0a5943de---55898790265.pdfIn PDF document text
    • http://dongzzang.com/userfiles/file///80567590131.pdfIn PDF document text
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb9a5221cb---xuxorepoxe.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/e2e94ddcfec35b0cebae02c0f486a0f5/51288155993.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/kodolajomifotigo.pdfIn PDF document text
    • http://wahluenfty.com/userfiles/migobadewaliraridox.pdfIn PDF document text
    • http://amexeuro.com/an3_Uploads/file/28325802117.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160982e0c77972---84108638188.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=being+made+redundant+whilst+on+furloughPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d619.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD619 11040 bytes
SHA-256: e1ef06e31fc9961c5361f4bd4d45c39c34a775dbf56b4573d839a16e5d75ac1f
font_01_sfnt_off0000ef73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF73 16392 bytes
SHA-256: b58abfe861856614f419179fae18cd52fe1da10613b613444e0f5d610063fe26
font_02_sfnt_off000119ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1