Malicious PDF — malware analysis report

Static analysis result for SHA-256 66e3a94bd386754f…

MALICIOUS

PDF

81.5 KB Created: 2021-03-21 04:58:52 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: 00acfd95510c4d7ab7eaa6552d059162 SHA-1: e33323b67d0bc79eda863a6ff2875187e766ee0d SHA-256: 66e3a94bd386754f1ce58668f34cd16385704edce31df1a2a8b22f4979506679
186 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by both ML classification and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to numerous external URLs, one of which is `https://ponafet.ru/award?keyword=bubble+sort+algorithm+in+java+pdf`. This suggests the document is likely a lure for phishing or to distribute further malware. The presence of many external links on disposable hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://ponafet.ru/award?keyword=bubble+sort+algorithm+in+java+pdf PDF link annotation
    • https://cdn.sqhk.co/bomemenun/heTjbtf/jesodikujo.pdfIn PDF document text
    • https://cdn.sqhk.co/lokiwejawe/Cjbhgie/37426753676.pdfIn PDF document text
    • https://wixurawitubeza.weebly.com/uploads/1/3/4/3/134319602/nebekixuvew-gimebenod-saxuz.pdfIn PDF document text
    • https://cdn.sqhk.co/poladejug/g1hljck/regosepipoda.pdfIn PDF document text
    • https://vewuwoxefi.weebly.com/uploads/1/3/1/3/131379256/romug-vazusajebemof.pdfIn PDF document text
    • https://cdn.sqhk.co/gilevetu/gBYiaWx/36459250814.pdfIn PDF document text
    • https://cdn.sqhk.co/nawakema/B5jjjzk/onkyo_hf_player_unlocker_apk_free_download.pdfIn PDF document text
    • https://pisanalanuju.weebly.com/uploads/1/3/4/3/134352438/soxufit.pdfIn PDF document text
    • https://cdn.sqhk.co/wujodazera/HjcvFgd/vebaxetolinemunot.pdfIn PDF document text
    • https://kunolutupevuj.weebly.com/uploads/1/3/4/7/134772201/8958062.pdfIn PDF document text
    • https://patoduwewoz.weebly.com/uploads/1/3/1/4/131483118/tumavonoxigosat.pdfIn PDF document text
    • https://cdn.sqhk.co/teposodigar/LifYijB/mars_volta_goliath_time_signature.pdfIn PDF document text
    • https://nunodovov.weebly.com/uploads/1/3/1/3/131380210/tufevizananokatupa.pdfIn PDF document text
    • https://cdn.sqhk.co/kotafuli/hgLgdgg/small_business_planner_near_me.pdfIn PDF document text
    • https://cdn.sqhk.co/kovixileta/hgidJjf/bleacher_report_wwe_live_updates.pdfIn PDF document text
    • https://pipulelinukebe.weebly.com/uploads/1/3/4/3/134364851/zudijavanosa.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/0732ec7f-b2af-46e2-b252-270f91866d81/nobelavetefe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/303c2b35-4b8d-44de-95af-49b65162fc1d/when_did_islam_start_in_africa.pdfIn PDF document text
    • https://dec4a425-646e-450a-80ca-a73a75d058ad.filesusr.com/ugd/ba3095_949cea7e22dd452f826e9721db8ef0db.pdf?index=trueIn PDF document text
    • https://4be8a7ba-6c9a-47a4-99fc-a5961b41a404.filesusr.com/ugd/132250_5cc5506354cc4fb1a4baa69bdfe85ea0.pdf?index=trueIn PDF document text
    • https://8f6f9f04-f977-4239-955d-f6aecf2dd879.filesusr.com/ugd/81cd61_34ebcd6b9d864acea1a25352904460e3.pdf?index=trueIn PDF document text
    • https://6d4cd3b7-91e9-43ac-92b9-205473f1e50d.filesusr.com/ugd/28146e_5894d05e54964b76a20ac9ac2d7a2f3a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e196d70d-3cf8-47e1-8aad-a806ce4510a3/how_to_check_my_caller_id.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_off0000fc72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC72 5780 bytes
SHA-256: 675646199b1cbdda26c1ab94c4e5288d1623c984f14debf1f87da782cb13ba5a
font_01_sfnt_off00010ffe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FFE 11980 bytes
SHA-256: ab94600c69674c2bf762e1dc1296d2648edeaa8e1243d56d2c185272c4108132