Malicious PDF — malware analysis report

Static analysis result for SHA-256 1dbbef9d59d467d5…

MALICIOUS

PDF

92.5 KB Created: 2021-03-01 17:24:52 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 259f3df870441daa8b28edd2ebcc7f27 SHA-1: 5cd4862da32f930e4eb79645e756742e44a923a2 SHA-256: 1dbbef9d59d467d55c098d5d9559071988412bf9cbb9260df982f441a7411d3b
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified by the PDF_SEO_LINK_FARM heuristic, suggesting a link farm or phishing attempt. The ClamAV detection and ML classifier also indicate maliciousness. While no scripts were explicitly extracted, the presence of numerous external URLs points towards an attempt to redirect the user to potentially malicious content, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 5

  • 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
  • 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://dafemum.ru/123?utm_term=machine+learning+algorithms+list+pdf
    • https://cdn-cms.f-static.net/uploads/4410013/normal_600cf26f74cd2.pdf
    • https://vafukomoruf.weebly.com/uploads/1/3/4/8/134862603/fd78ef39cb.pdf
    • https://cdn-cms.f-static.net/uploads/4484804/normal_603c834398111.pdf
    • http://cparta.moscow/47421555570cfz29.pdf
    • https://cdn-cms.f-static.net/uploads/4490128/normal_5fdc14cab145f.pdf
    • http://shoop-fl.ru/dell_r740_server_datasheetwnd86.pdf
    • http://pasendapp.online/bezomavovaroxomitixirufuc2zeb.pdf
    • https://static.s123-cdn-static.com/uploads/4480155/normal_5ffb3ef68e644.pdf
    • https://cdn-cms.f-static.net/uploads/4489844/normal_600fbe55c2ae5.pdf
    • https://static.s123-cdn-static.com/uploads/4497369/normal_5fc89bbae44f8.pdf
    • https://cdn-cms.f-static.net/uploads/4465249/normal_6029c5b7775b4.pdf
    • https://static.s123-cdn-static.com/uploads/4456391/normal_6004f01ea4014.pdf
    • http://50offshop.pro/facebook_android_desktop_ansicht038ky.pdf
    • https://static.s123-cdn-static.com/uploads/4418383/normal_6003713b71598.pdf
    • http://rijazozetofovi.22web.org/dark_souls_2_hex_build_guide.pdf
    • http://mugafopame.iblogger.org/49282543070.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://tejugezefufuli.rf.gd/zaguk.pdf
    • http://zavatuwobo.rf.gd/what_is_meant_by_isentropic_flow.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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012bd8.bin
9027a08a91f5ca9c3277bf3e1ed6bd0ed60d8a96c810fea0facb71b8cca47788
pdf-font-stream PDF embedded font (sfnt) at offset 0x12BD8 5572 bytes
font_01_sfnt_off00013eb0.bin
acf088db08a1c6767dbef87f65a624e9c2936a249b9e482de9ebd52cb17ff525
pdf-font-stream PDF embedded font (sfnt) at offset 0x13EB0 11072 bytes