Malicious PDF — malware analysis report

Static analysis result for SHA-256 aae633103344dec6…

MALICIOUS

PDF

75.7 KB Created: 2021-03-24 05:47:09 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cb32ba63f703be1852a5ac79e0e35fe8 SHA-1: d47f609f01d71a1b5589014116fbf78c4e273799 SHA-256: aae633103344dec6e49140179071297042fd0ceccfde953991a82874ae9b4ee1
194 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as 'Pdf.Phishing.Trojan'. The presence of a 'download button' heuristic further supports the lure aspect of the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 7

  • 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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://seumenha.ru/award?keyword=emoji+printables+black+and+white+pdf
    • https://cdn-cms.f-static.net/uploads/4406785/normal_605a8034264e9.pdf
    • https://cdn-cms.f-static.net/uploads/4424666/normal_600cb4497d66f.pdf
    • http://dumigegin.medianewsonline.com/26371843077.pdf
    • https://cdn-cms.f-static.net/uploads/4445743/normal_601f83daea950.pdf
    • https://cdn-cms.f-static.net/uploads/4502336/normal_60584150a96c4.pdf
    • http://vijepuwobewi.mygamesonline.org/sovolaguxewededugiwupimi.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://95c758d6-fd33-43c6-b5d0-f1f55e07e946.filesusr.com/ugd/cb0188_ac043018d7ab467d8aabba1099e7b4b2.pdf?index=true
    • https://59b7e61f-9850-45ee-add2-e9646db267e4.filesusr.com/ugd/5b9365_40b8bf48934f4304bd727a15a9994efd.pdf?index=true
    • https://uploads.strikinglycdn.com/files/74b79349-e956-48f7-bf68-caeeba9ea2dc/audre_lorde_short_stories.pdf
    • https://9d3edb37-11ce-4d87-b861-4f8d850d55a0.filesusr.com/ugd/0d2aa0_47f51d476ace47e6b9f75dbeca1bc09c.pdf?index=true
    • https://4c5ad993-366d-4b3a-aa99-9b6f56583180.filesusr.com/ugd/01e791_e0c232b012bb43baa6886972c8f3a0de.pdf?index=true
    • https://uploads.strikinglycdn.com/files/aca72738-5d30-4135-8448-ed39ebb39b14/how_often_do_you_replace_roomba_battery.pdf
    • https://945c5b1a-9feb-4a08-b72d-c905ca1b1520.filesusr.com/ugd/27135d_5415c555f54647f99d66a61e9422e9ef.pdf?index=true
    • https://uploads.strikinglycdn.com/files/61a0b33d-d3ff-4cf8-ab72-4313b0fe4993/77237976278.pdf
    • https://uploads.strikinglycdn.com/files/b8ec4d57-b777-45d0-ac05-35ea497ea5ae/psychological_tests_for_anxiety_and_depression.pdf
    • https://5ce19dfa-329f-495d-88d1-e1e7834d9072.filesusr.com/ugd/d902bb_f9d755de905c4ba0b8699c8e62f86e07.pdf?index=true
    • https://c6f55193-7475-4343-97dd-33cb3b141b6a.filesusr.com/ugd/808d8c_ffff484d1ce14732bdff014a2fede3af.pdf?index=true
    • https://uploads.strikinglycdn.com/files/6c46af20-02d1-458b-8305-f773ebdbf2d4/what_is_literary_devices_in_poetry.pdf
    • https://0dd0cd87-80d3-4eb5-b9c6-73c43c3a6fca.filesusr.com/ugd/f0b6b3_7e4dc77754b3482b89fdf137535ba55c.pdf?index=true
    • https://413f70bc-0247-4a04-a3fc-eabb14e2b93f.filesusr.com/ugd/f18ee6_06c62f2c628241dc830b7f3b2d598e2b.pdf?index=true
    • https://c81c1a69-aec6-471c-ac34-7a6800eafc69.filesusr.com/ugd/9ef1ea_16cd383dd37f4ae69bb92611868d6300.pdf?index=true
    • https://ce2645ba-e89a-43d5-afff-5c0150757291.filesusr.com/ugd/c63dba_b4d73fc3c63b4034a5d9b2007097a491.pdf?index=true
    • https://f4a80ce2-0a24-44e2-aff7-13c87a434ee9.filesusr.com/ugd/ace063_dc86716a67cd45208f45509bdd035fbb.pdf?index=true
    • https://696f1bd8-06c3-47a7-a8f7-e83e17ec8d18.filesusr.com/ugd/5ad03d_7dad0cfe40f14f448eb5ba40b9664b2a.pdf?index=true
    • 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_off0000e642.bin
652d55da7dfd21cee54c88d9c11ca9e025490ae40f1ac88743dd44e5ce118692
pdf-font-stream PDF embedded font (sfnt) at offset 0xE642 5724 bytes
font_01_sfnt_off0000f9a3.bin
73796a7a27c0efff86ac21372cc59645a554f7b2dcd1562e7a6d00ff2d7d27a2
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A3 11208 bytes