Malicious PDF — malware analysis report

Static analysis result for SHA-256 31c97d8632185ecf…

MALICIOUS

PDF

80.8 KB Created: 2021-03-28 20:18:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: d53003c90baf69fdd6512a6bf1079dd4 SHA-1: 643ea98da4bd7bf2e65332cdde7912ecd7836c0e SHA-256: 31c97d8632185ecf0b0895edf0874957fbce789633099883851661366fe9d1ba
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it contains a large number of external links, forming a link farm, with one prominent URL being https://xezojetit.ru/award?keyword=reading+comprehension+activities+pdf. This suggests the document's primary purpose is to direct users to a network of other sites, potentially for SEO manipulation or to serve further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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 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://xezojetit.ru/award?keyword=reading+comprehension+activities+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4374980/normal_603953462523f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454422/normal_60166511b5485.pdfIn PDF document text
    • http://xakuneferufilew.iblogger.org/bin_sachivalay_clerk_model_paper.pdfIn PDF document text
    • https://liwitozawaben.weebly.com/uploads/1/3/4/0/134042828/zozexa-bivamamaz-kidilogesezu-xiluwo.pdfIn PDF document text
    • https://wedutigumufezeb.weebly.com/uploads/1/3/4/6/134659425/damenelovixu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484609/normal_603915958cc11.pdfIn PDF document text
    • http://alesyasemiletova.com/how_much_is_sandalwood_worthkj9ik.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376382/normal_5fd9060f2bbdb.pdfIn PDF document text
    • https://faxomozux.weebly.com/uploads/1/3/0/7/130775398/dikijinowi_funatizexor_nilum_taputizubalaxof.pdfIn PDF document text
    • https://vugigedekamem.weebly.com/uploads/1/3/4/3/134339685/xubirad_pobisafarasopo_kinujagul.pdfIn PDF document text
    • https://murezujal.weebly.com/uploads/1/3/5/3/135305344/3258659.pdfIn PDF document text
    • http://copyrightsupport-ig.com/club_car_golf_cart_charger_plugtf78o.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/02a443c8-ee30-4198-8f12-c67898198e82/hp_deskjet_3050_driver_download_windows_10.pdfIn PDF document text
    • http://xoxitazowakovit.rf.gd/54189999393.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/00b73ea2-a1bb-4881-9256-95ca40464b0a/51413307767.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2a783b53-8c26-4159-a47a-83467c55e853/getak.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b0232f40-fff4-44b1-b1a2-5234779d2b1d/swing_trading_for_dummies_amazon.pdfIn PDF document text
    • http://kojokiguxan.epizy.com/pekexubejato.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0d349d48-bf2e-4c42-89ff-69f856bbe929/husky_air_scout_compressor_model_41004_manual.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fe1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE1F 5604 bytes
SHA-256: 83ed3dcfb6536786b7b15bbee15680cc25636f1066bf88aa5b180e9209ae607d
font_01_sfnt_off00011116.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11116 10912 bytes
SHA-256: 5f6c748001011983c84cd32a2c1c4b2dd046c6d1d4b7ac068ff8370215fdaffe