Malicious PDF — malware analysis report

Static analysis result for SHA-256 8123453bb914f1a5…

MALICIOUS

PDF

70.0 KB Created: 2021-03-15 19:51:13 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-17
MD5: 68ca10ec7d46c68aa8456efd370d8e31 SHA-1: 17d6e1559dd88038b5d48957412384a00443ca7e SHA-256: 8123453bb914f1a5a65c4c600c0f8c7467d73f0106e564b896d29cd3f24e6d0d
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous external links to other PDF documents hosted on various domains, some of which appear disposable. The primary URL, 'https://xajibur.ru/wix?keyword=kuta+software+infinite+algebra+2+graphing+exponential+functions+answers', suggests a potential SEO manipulation or phishing lure. The presence of multiple external links and the disposable hosting of some PDFs point towards an attempt to distribute further malicious content or engage in deceptive practices.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://xajibur.ru/wix?keyword=kuta+software+infinite+algebra+2+graphing+exponential+functions+answers PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4487916/normal_5fe3fbb603c4f.pdfIn PDF document text
    • https://cdn.sqhk.co/nudizodi/ighaeih/42239145447.pdfIn PDF document text
    • https://cdn.sqhk.co/munenetifu/jA2ojhA/capitulo_5a-_8_crossword_answers.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406789/normal_603a9b0a51ae7.pdfIn PDF document text
    • https://nimidakotogala.weebly.com/uploads/1/3/0/8/130874585/a02dfc13d.pdfIn PDF document text
    • https://cdn.sqhk.co/zezetemirag/DzYPiid/police_ringtones_free.pdfIn PDF document text
    • https://dobamadolexazi.weebly.com/uploads/1/3/4/4/134478964/vodug.pdfIn PDF document text
    • https://xomitemekebok.weebly.com/uploads/1/3/4/8/134881854/tobolufinedulet_zizux.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384029/normal_6006f01fc8b68.pdfIn PDF document text
    • https://golasirase.weebly.com/uploads/1/3/1/3/131384643/5416001.pdfIn PDF document text
    • https://cdn.sqhk.co/wuvinudubuno/t8iglih/final_fantasy_4_wiki_characters.pdfIn PDF document text
    • https://cdn.sqhk.co/sezepemanu/tgfjfhb/turbo_kit_for_toyota_tacoma.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://fab88ded-2f12-46c9-b6ec-f290036286cc.filesusr.com/ugd/cce69c_2103f56a9cb84ed691423d5d5a586e30.pdf?index=trueIn PDF document text
    • https://ce419959-236d-4487-89d7-67f356bda573.filesusr.com/ugd/147b51_01813974ab4a4f729fadb1216d71d86c.pdf?index=trueIn PDF document text
    • https://cd489911-dc6d-4439-b408-84622343fb93.filesusr.com/ugd/d8e941_73f0e1e9223349718caa7b2b7f962a8f.pdf?index=trueIn PDF document text
    • https://cb6d8354-940b-4e05-9f1d-0150973ab277.filesusr.com/ugd/882da0_5719c9ff577d4459ac47b1963a1c45eb.pdf?index=trueIn PDF document text
    • https://1801fa0f-56e4-4894-8452-b8e06651d4be.filesusr.com/ugd/868401_2420991aac5344e292907bda02d82eee.pdf?index=trueIn PDF document text
    • https://c5c27394-2042-4749-9b39-d1c24dcbd9f0.filesusr.com/ugd/e9b987_85fd00633e914836981f786a53b9744c.pdf?index=trueIn PDF document text
    • https://746420f6-3007-491b-ba72-fd43be5094e5.filesusr.com/ugd/277b62_7961bcf1cf1847a9addc2bdb5a2527d5.pdf?index=trueIn PDF document text
    • https://59cf682b-6680-4a08-8b8d-0472bab64ef7.filesusr.com/ugd/d7d6cd_95a8ec031b90421f860bcc6b88fe35b6.pdf?index=trueIn PDF document text
    • https://1d812fcc-cfc3-4558-a870-56fc5b7f4c2e.filesusr.com/ugd/754d94_51df3f5a91b04945aa42727fbc91621a.pdf?index=trueIn 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_off0000d06c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD06C 5676 bytes
SHA-256: 2195dfaa5cb1698df04a3610fac6d594dc855c03aa8b44d16d05864fc35a2afe
font_01_sfnt_off0000e3de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3DE 10544 bytes
SHA-256: ddb63ccf4fc2108135c347d8b002660f6dd07332a19c28ab7600fcf707546585