Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8126ee7ca544085…

MALICIOUS

PDF

73.6 KB Created: 2021-03-28 07:59:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 496f6704504b58d5bc7707b75dc917f1 SHA-1: ad02da78a6a0086b69b99c8e83a9b89434edade5 SHA-256: b8126ee7ca544085f6bbaf6e4705e3e616d8e65bcf334eeb6ad81be91ca78662
214 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by multiple heuristics, including a critical finding for linking to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains text related to 'Christmas medley piano sheet music pdf' and the authoring application 'wkhtmltopdf', suggesting a lure. The presence of numerous external links, including one to a known malicious redirector, indicates an attempt to lead the user to a harmful site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9900

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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 differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://yafferge.ru/award?keyword=christmas+medley+piano+sheet+music+pdf
    • https://cdn-cms.f-static.net/uploads/4455176/normal_60570b5aadf56.pdf
    • https://cdn.sqhk.co/gixenako/g8rlfwl/vsco_mod_apk_v76.pdf
    • https://levalezekavazif.weebly.com/uploads/1/3/4/6/134639406/woduderozaxa_vadiwewi_woburefexopige.pdf
    • https://cdn.sqhk.co/mizogujuzo/4jbkvOx/fadaxivukinasivinuk.pdf
    • https://static.s123-cdn-static.com/uploads/4415742/normal_5fe55f33e3bf5.pdf
    • https://static.s123-cdn-static.com/uploads/4501233/normal_60038a378f4b2.pdf
    • https://cdn.sqhk.co/nivuduful/xjauheo/xisanefili.pdf
    • https://cdn.sqhk.co/boguzivipel/cZhcvEt/tigipukuparusomobifogib.pdf
    • https://cdn.sqhk.co/gitaligido/kijBjaJ/51828405190.pdf
    • https://cdn.sqhk.co/gofejenizew/jhdgjGi/kingdom_hearts_1._5_wiki_guide.pdf
    • https://cdn.sqhk.co/mixitebumu/idiahiS/real_steel_movie_trailer_2011.pdf
    • https://cdn.sqhk.co/lazimafuxuxi/fIhizhe/bigbang_kpop_quiz.pdf
    • https://xufolonul.weebly.com/uploads/1/3/2/6/132695880/06f8edf1.pdf
    • https://static.s123-cdn-static.com/uploads/4367940/normal_5ff29e7e1da66.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/53dd9911-6547-4978-832e-479898405ae1/partner_bodyweight_workout_crossfit.pdf
    • https://uploads.strikinglycdn.com/files/ebdeddb4-f9f2-4b0e-b6a6-e524b67fbcb3/97523315399.pdf
    • https://uploads.strikinglycdn.com/files/d5c95cfd-4a77-4d2b-95db-c368e03a6588/68776735836.pdf
    • https://uploads.strikinglycdn.com/files/8a6f90c7-5398-4a8a-b137-62b903e45169/oculus_architecture_def.pdf
    • https://uploads.strikinglycdn.com/files/4c946f66-a582-48c4-b3a5-99db08757ee7/bartletts_familiar_quotations.pdf
    • https://uploads.strikinglycdn.com/files/0549c485-b2f8-4da3-a21c-9f0abeb61aaf/why_are_your_personal_narratives_important.pdf
    • https://uploads.strikinglycdn.com/files/2f65a48d-1b1e-480a-b3f4-ccf5dc4e6693/how_to_fix_bose_3_cd_changer.pdf
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec92.bin
879b04b229c7f3c6a7894e50811bb066b76b2c3a1fc6888249dde92d09035e3f
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC92 5404 bytes
font_01_sfnt_off0000fec9.bin
0367d322a0cd4a3573e0e40d4c64ba9be0ea87d7ce1016baff8d4630ff3258e3
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEC9 10744 bytes