Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3c387405c6b755f…

MALICIOUS

PDF

89.4 KB Created: 2021-02-25 00:04:52 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 91b31b66f49990d9c1c3f98215a2e55c SHA-1: 05401294c7c51fd568d4c36b03e59b2c4b9672e9 SHA-256: f3c387405c6b755f820a2175d543fab0b76b4b8f56b84e3e50b2980c27896c0f
186 Risk Score

Malware Insights

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

This PDF file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO spam operation. The primary URL, 'https://jacksth.ru/123?utm_term=el+cantar+del+mio+cid+anaya+pdf', is presented as a search result, likely to deceive users into clicking through to malicious content. No scripts were extracted, but the PDF structure itself is used to host and distribute these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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.
  • 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://jacksth.ru/123?utm_term=el+cantar+del+mio+cid+anaya+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4401989/normal_5ff26105d9f5e.pdfIn PDF document text
    • https://cdn.sqhk.co/pozigafo/uQhg3em/contact_lenses_halloween_amazon.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465257/normal_5fe57b80ddf5d.pdfIn PDF document text
    • https://cdn.sqhk.co/riroxale/dDzNVnJ/95667542291.pdfIn PDF document text
    • https://regogugone.weebly.com/uploads/1/3/4/8/134891767/7954560.pdfIn PDF document text
    • https://nakigere.weebly.com/uploads/1/3/4/6/134608851/xeroxajaj.pdfIn PDF document text
    • https://xowogibudul.weebly.com/uploads/1/3/4/4/134446034/919e7de61b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378165/normal_602d35438e685.pdfIn PDF document text
    • https://bejokezogakuji.weebly.com/uploads/1/3/2/6/132695802/buloxew.pdfIn PDF document text
    • https://cdn.sqhk.co/bapisolel/fWbXylB/29478390684.pdfIn PDF document text
    • https://cdn.sqhk.co/fefamuve/hidDgdd/24366778087.pdfIn PDF document text
    • https://cdn.sqhk.co/talexadu/GgcrmKr/video_voice_changer_fx_mod_apk.pdfIn PDF document text
    • https://gazumewus.weebly.com/uploads/1/3/4/9/134901575/1912806.pdfIn PDF document text
    • https://pamuguvijokogag.weebly.com/uploads/1/3/4/8/134883264/lidilekew-jiwakelevemi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448713/normal_602456b182773.pdfIn PDF document text
    • https://mesupajediruz.weebly.com/uploads/1/3/6/0/136051454/gajov.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/midaguvimabof/15935590601.pdfIn PDF document text
    • https://s3.amazonaws.com/wizakokowe/angular_2_template_driven_forms_validation.pdfIn 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
    • 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_off00010867.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10867 5180 bytes
SHA-256: f62ba825951858850daa5fcea91724748281b0d356c093d080008dbf25a75de8
font_01_sfnt_off00011a01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A01 12156 bytes
SHA-256: 23f6ea3a2211650c9317890a2f14f9d65d1a89ddc443862131ee67438c286709
font_02_sfnt_off00014137.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14137 16280 bytes
SHA-256: cf5d09669545a3493627c2db5e7d9490bfed5c871057eec6c30e9ed69bb14e59