Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fd6714b5e936ede…

MALICIOUS

PDF

87.0 KB Created: 2021-03-09 07:38:27 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 82c15ab60a17f6ee06f1772dafe54034 SHA-1: f4ad7fe57f5e6440ae133782329d690f4c2bef02 SHA-256: 8fd6714b5e936ede72aeb41a116c215b9c8802109978d78729a48df33876086c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable hosting, with numerous embedded URLs pointing to potentially malicious sites. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a chapter summary, suggesting a lure to a fake content page.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://jottigo.ru/wix?keyword=son+of+the+mob+summary+chapter+10 PDF link annotation
    • http://fbcopyright-center.com/ensayo_del_seor_de_las_moscasa9v08.pdfIn PDF document text
    • http://justiciaforjustice.com/pefomukaxupobutp3l64.pdfIn PDF document text
    • http://tekdouche.xyz/history_of_kashmiri_panditsmign3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485176/normal_600b9b5e24721.pdfIn PDF document text
    • http://cloudplay.xyz/silicon_valley_power_service_connect_charge2w9vz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372073/normal_600fd752a2936.pdfIn PDF document text
    • http://goodik.fun/73867708720j0l1n.pdfIn PDF document text
    • http://creampiepow.club/can_the_protagonist_be_evilzkgr0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424996/normal_602db351760ee.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425514/normal_6041f5cb68e30.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4444366/normal_5fc6935b5abcb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4498842/normal_5ff429115fc97.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366377/normal_5fd8d48a06d55.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413975/normal_5ffce1f41c506.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417046/normal_600c6fae53d4a.pdfIn PDF document text
    • http://grusha.space/apsara_sadhana_book_downloadeqfli.pdfIn PDF document text
    • http://trysoda.pro/final_fantasy_x-2_strategy_guidees54d.pdfIn PDF document text
    • http://com-signto5.xyz/tango_blast_ganglandk1xv6.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://ff06b2c9-6223-4357-b4d5-1bf3807c749f.filesusr.com/ugd/717131_21cadd35aefd4940b8135efbc5a06159.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/99506fdc-2a8d-4e59-9a36-4bc4736d27be/dowudifotefixapuku.pdfIn PDF document text
    • https://6648aa49-deb3-4d6f-81a8-a63cc7a297fb.filesusr.com/ugd/38eac1_b3575c5f244c4414817db2e81711c904.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a2150192-70f2-4afd-a498-3c8f8c06353a/69573572935.pdfIn PDF document text
    • https://e9abb47e-19e5-4ec2-9f3c-2aa4e6f2bf0a.filesusr.com/ugd/92be99_ac221055d2134f8688a631a97a5befdb.pdf?index=trueIn PDF document text
    • https://a2ae8793-a99f-480d-a3bc-849ef63d34f7.filesusr.com/ugd/cc207a_bdd3d3abf2df402987455089fe01f8d5.pdf?index=trueIn PDF document text
    • https://ba85394b-11ac-4ca4-926b-74ca936c52e1.filesusr.com/ugd/5ccfc8_78f3f7d56dc44f4284b8973777540b05.pdf?index=trueIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000117ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117CE 5764 bytes
SHA-256: 753aaecfefc7916cb7748175cfbb3e81c459423fc7951629c8c1303468729bdc
font_01_sfnt_off00012b50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B50 10312 bytes
SHA-256: 3068f99918c8b2a664376350f979a133031e14db0ae6f6a0a33eabe7e1120dd4