Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cc541d11f8e8ef5…

MALICIOUS

PDF

88.1 KB Created: 2021-02-27 15:54:42 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: de7b8667a49f4f79d4233b584c544362 SHA-1: 2903464f17c93363b7d6b31e085c829ce0eaf616 SHA-256: 3cc541d11f8e8ef566000fae5f3ddeda3a7cd7c449750c19a93bcadb37fb9d45
244 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, and contains numerous embedded links. One critical heuristic indicates that the PDF links to known malicious redirector infrastructure, specifically 'https://yafferge.ru/strik'. The document body, though heavily obfuscated, appears to contain text related to graphs, suggesting a potential lure for technical or academic users. The presence of many external links, some on disposable hosting, strongly suggests a link farm or phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/strik?utm_term=how+to+get+velocity+time+graph+from+position+graph In PDF document text
    • https://cdn.sqhk.co/ximegawaso/gggBnIw/97624372819.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454302/normal_5fdd7628735b2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477878/normal_60323e28135cd.pdfIn PDF document text
    • https://dosidebeg.weebly.com/uploads/1/3/5/3/135318632/zufadopato.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403128/normal_5fd68590d8411.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446390/normal_602a14234bd1b.pdfIn PDF document text
    • https://cdn.sqhk.co/nokotadi/Khju1gd/big_baby_taylor_guitar_center.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420260/normal_6016155231099.pdfIn PDF document text
    • https://cdn.sqhk.co/tixukiko/szCbjh8/home_alone_movie_cast.pdfIn PDF document text
    • https://dapasubasawesol.weebly.com/uploads/1/3/4/3/134383907/9919814.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454306/normal_60030b4320928.pdfIn PDF document text
    • https://cdn.sqhk.co/medugagoviji/eOiegiS/bet_dynamo_free_trial.pdfIn PDF document text
    • https://lawuzifelive.weebly.com/uploads/1/3/4/0/134041442/133281.pdfIn PDF document text
    • https://mepopukivar.weebly.com/uploads/1/3/6/0/136083549/zejesinumudem.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/gozilum/56240248007.pdfIn PDF document text
    • http://zezexobufimorum.epizy.com/adb_start_android_settings.pdfIn PDF document text
    • https://s3.amazonaws.com/bajuse/female_hypogonadism_treatment_guidelines.pdfIn PDF document text
    • https://s3.amazonaws.com/litunux/82238442463.pdfIn PDF document text
    • http://laxakufas.epizy.com/nota_van_toelichting_bouwbesluit_2012.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000102a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102A9 2900 bytes
SHA-256: a28fcc4ba65d8171a55e8b87d646ac5d1dd213f66ab2b0026fd39e5ca5d32d1a
font_01_sfnt_off00010ceb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CEB 5432 bytes
SHA-256: 79029a49133a2f948efa07db7d02031d9571e6556dee1a20566972c2db0bcd30
font_02_sfnt_off00011f58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F58 10816 bytes
SHA-256: d8f4477fc2976fce653ac737e2b7fae5ec28e8363c02d5cd84bfd31de8909fd8
font_03_sfnt_off0001444d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1444D 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333