Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9c1a5181ebb31c8…

MALICIOUS

PDF

76.0 KB Created: 2021-04-25 23:28:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: b79974ad9a03bb5138c68de224594aa8 SHA-1: 808a85be833aefc00602fbbd5f7ac3059e6e61bd SHA-256: d9c1a5181ebb31c88ac39b05fe3aadb46d6d665b7bc2425b8d3e58e6004d155d
226 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • 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.
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://jumiwimov.ru/strik?utm_term=how+much+does+an+electrical+engineer+earn+in+usa PDF link annotation
    • http://meetchambre.xyz/fejegipinowiwewojegekalit5x1rk.pdfIn PDF document text
    • http://vashmaster.info/how_to_check_out_a_used_car_before_buying_itucwuc.pdfIn PDF document text
    • http://lipenav.mypressonline.com/95741473382.pdfIn PDF document text
    • https://vobawele.weebly.com/uploads/1/3/5/3/135334277/ralovaxipude.pdfIn PDF document text
    • http://jerugujekema.getenjoyment.net/sedumaroxulukobixi.pdfIn PDF document text
    • http://erogan24.website/ritual_sacrifice_goat_simulator_ps4exgra.pdfIn PDF document text
    • http://carinsusa.info/spectrum_math_workbook_grade_8_free92cvz.pdfIn PDF document text
    • https://zotejukewas.weebly.com/uploads/1/3/5/3/135347558/xunuxokobegopi.pdfIn PDF document text
    • http://mnogoturov.com/subewigipologogifaximitipj71z.pdfIn PDF document text
    • http://uscovidcharts.com/gosotozon7kih.pdfIn PDF document text
    • http://sodahub.pro/widenesovirapewulcm4ec.pdfIn PDF document text
    • https://gifukupuwabe.weebly.com/uploads/1/3/0/7/130775529/5907015.pdfIn PDF document text
    • http://about-central.com/75313527200lulb7.pdfIn PDF document text
    • http://gouliwer.online/ryobi_table_saw_extension_kit9uyft.pdfIn PDF document text
    • http://nonretloli.site/7638179067789am2.pdfIn PDF document text
    • http://help-lnstagram-verifycopyrgiht.com/377607634346uz7.pdfIn PDF document text
    • http://ipoteka.net/sefekefutisazozufulozutusfddbe.pdfIn PDF document text
    • https://wulapoledonuker.weebly.com/uploads/1/3/2/6/132695240/de458.pdfIn PDF document text
    • http://reassurez-moi-fr.info/239807674697bpo7.pdfIn PDF document text
    • https://zivumipit.weebly.com/uploads/1/3/4/3/134317334/nadelerovizumuw_bafajuvekafas_gadur.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://434dcbc4-7bd9-40fe-99bf-e102daebf961.filesusr.com/ugd/07ef24_26db6331fd67423ca3c354364225c9a4.pdf?index=trueIn PDF document text
    • https://d89d6b52-6e76-4e18-bccb-bd7428cfddad.filesusr.com/ugd/02beb7_386eae9669214754a1401fb0a6b2ac4a.pdf?index=trueIn PDF document text
    • https://eaae50f7-3b1c-4f1b-9b3c-e2a48377569d.filesusr.com/ugd/b96e41_949246ec5a67419690e5a6aea2e02e95.pdf?index=trueIn PDF document text
    • https://2a07c75e-e898-48ba-b326-4cccc82d0599.filesusr.com/ugd/ff154e_9c8bbb1d322c4be5b96aa4d9907698b5.pdf?index=trueIn PDF document text
    • http://geforagegi.atwebpages.com/doxixavif.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_off0000eb54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB54 5408 bytes
SHA-256: 7b4f9b1d8a0a0548d163cad4dd0cbddf98b123ebf02804c0530cc4b0ec861e10
font_01_sfnt_off0000fd95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD95 10592 bytes
SHA-256: 37296a7e56167d9497d3e097755b930386f694359c9a2395cbf7b7892b1bebc0