Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4bf8ded77132119…

MALICIOUS

PDF

81.5 KB Created: 2021-03-17 11:37:02 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2e83173e0c893a8f82a6af332a6cc07d SHA-1: e3e1e548e00b3bdbd3d49d6b9aed1e84b4d1d510 SHA-256: c4bf8ded77132119687d825c493db811d053a3c4a313844fb4ecf5a0968fcbb7
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are SEO-optimized to appear as legitimate documents, indicating a link farm or phishing attempt. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://druttle.ru/award?keyword=antenna+definition+pdf
    • https://cdn.sqhk.co/saboxiwago/ivjjDoV/lidudazumoxo.pdf
    • https://cdn-cms.f-static.net/uploads/4487647/normal_603eebc87a179.pdf
    • https://miravavomi.weebly.com/uploads/1/3/1/4/131410597/gujejiwajuvigo.pdf
    • https://cdn.sqhk.co/letinumi/tgeoa9T/how_to_get_zombie_slayer_doom_eternal.pdf
    • https://cdn-cms.f-static.net/uploads/4393628/normal_5fda65a1cd74d.pdf
    • https://cdn-cms.f-static.net/uploads/4468289/normal_604cdf7c32adc.pdf
    • https://cdn.sqhk.co/jawuraxexije/BOhbLif/goosebumps_night_of_scares_game_download.pdf
    • https://kiwakobomu.weebly.com/uploads/1/3/1/4/131482833/954530.pdf
    • https://gonewama.weebly.com/uploads/1/3/4/0/134095907/figetob.pdf
    • https://cdn.sqhk.co/nukusigemug/7idiiG6/70839068084.pdf
    • https://cdn.sqhk.co/sigidezok/bO24geb/physics_kinematics_worksheet.pdf
    • https://panikelixiguju.weebly.com/uploads/1/3/4/4/134478359/seravi_xipupajo.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/wopari/microsoft_cortana_apk_espaol.pdf
    • https://77abcf6a-1f47-4233-a5f7-28832101be0a.filesusr.com/ugd/e29e5c_467fde534ee0481fb4b69bcd3c576631.pdf?index=true
    • https://s3.amazonaws.com/wokesabisevo/new_canada_food_guide.pdf
    • https://5a20c861-23fd-468b-888e-078c5342874f.filesusr.com/ugd/924841_e22188fb4bb54c8fb42b8ae7d0950ba0.pdf?index=true
    • https://204833c8-abda-4421-8777-5048ee7dd919.filesusr.com/ugd/e30b7a_1d2640f8bf424042a00c929548673366.pdf?index=true
    • https://s3.amazonaws.com/lawakux/why_is_my_jbl_speaker_not_connecting_to_my_iphone.pdf
    • https://8b83d164-5e56-46cc-b941-48f48810ddf3.filesusr.com/ugd/76ce43_19570a9a05b24524a4e21be459350f5d.pdf?index=true
    • https://6b137298-3864-41c5-aaa3-11744000c3c2.filesusr.com/ugd/b916f4_11038bdd22134ae08591816ec2019196.pdf?index=true
    • https://s3.amazonaws.com/migivewuwe/yellow_bell_flowers_images.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f69e.bin
cfa9f669f4a4a2bd82989ae7b3019139eb42b144c8db7ca115feaeadbe4a1345
pdf-font-stream PDF embedded font (sfnt) at offset 0xF69E 4508 bytes
font_01_sfnt_off000105fc.bin
09a8123bb2d96c8229687077c75059d3b9f789c24e2dcb2ababe6dca19b032d5
pdf-font-stream PDF embedded font (sfnt) at offset 0x105FC 10776 bytes
font_02_sfnt_off00012a58.bin
1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A58 4324 bytes