Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8d5a7e765d81272…

MALICIOUS

PDF

88.5 KB Created: 2021-06-05 15:30:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b9219a5bc7ae56be4ea66d33d05fd6e6 SHA-1: 6547c037c67ef1cecc2527c90024623dc9eb5da5 SHA-256: d8d5a7e765d81272fe05646f98d08df2504ae0e63bfcd480cacb772c5b832294
214 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of external links, many hosted on disposable domains, indicative of a link farm. Heuristics like 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggest this is not legitimate content. The presence of 'SE_INVOICE_LURE' and 'SE_CALLBACK_LURE' heuristics further supports a phishing or scam intent, aiming to trick users into clicking malicious links. ClamAV also detected this as 'Pdf.Phishing.Trojan'.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

Heuristics 8

  • 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.
  • 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 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://nomylo.ru/pbw?utm_term=how+long+does+it+take+centrelink+to+process+youth+allowance
    • https://static.s123-cdn-static.com/uploads/4416935/normal_6008d5b02bfd3.pdf
    • https://zopogunonezaso.weebly.com/uploads/1/3/1/6/131637395/gexaluzugowigo_tigonuduretuf.pdf
    • https://lewebivaduxug.weebly.com/uploads/1/3/5/3/135392118/4865185.pdf
    • https://daxozeke.weebly.com/uploads/1/3/4/3/134322415/3008560.pdf
    • https://cdn-cms.f-static.net/uploads/4380869/normal_6033c4925d69a.pdf
    • https://cdn-cms.f-static.net/uploads/4450864/normal_603ff6e2245fa.pdf
    • https://parukiwodisurup.weebly.com/uploads/1/3/4/4/134455528/mefojinopelodi-kixixirexafe.pdf
    • https://begosibaluta.weebly.com/uploads/1/3/0/7/130775163/bepuzonadoj.pdf
    • https://dizugupixaxagoj.weebly.com/uploads/1/3/4/4/134440249/titukuwub.pdf
    • https://tosojeravi.weebly.com/uploads/1/3/4/6/134617838/pujemut.pdf
    • https://tizijepen.weebly.com/uploads/1/3/4/2/134234944/boxezoge.pdf
    • https://cdn-cms.f-static.net/uploads/4375514/normal_603bed4e31b09.pdf
    • https://cdn-cms.f-static.net/uploads/4461746/normal_6052f86e23857.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/1186fc28-2078-436e-86a1-42f75b627a88/act_practice_test_1165d_answers.pdf
    • http://nilanom.pbworks.com/w/file/fetch/144416151/troubleshooting_scansnap_s1300i.pdf
    • https://uploads.strikinglycdn.com/files/5844e85b-3fe4-4613-a864-d3f2201f8933/jabubewaba.pdf
    • http://redejok.pbworks.com/w/file/fetch/144520800/wedding_card_matter_in_english_for_daughter.pdf
    • http://kiletejude.pbworks.com/f/libros_de_harry_potter_originales_en_espaolo.pdf
    • http://bevojoluvu.pbworks.com/f/where_can_i_find_kanais_cube_in_diablo_3_ps4.pdf
    • http://bezawagiga.pbworks.com/w/file/fetch/144601044/dirt_devil_power_max_pet_instructions.pdf
    • http://luwapoveduvi.pbworks.com/w/file/fetch/144661104/how_to_megger_test_a_cable.pdf
    • https://uploads.strikinglycdn.com/files/aa51a28d-3cee-47c6-a77b-0743af02d68e/sapataria_carocha_catalogo_de_cuentas_sat.pdf
    • http://kivotin.pbworks.com/w/file/fetch/144550380/pukizakutimelozupuji.pdf
    • http://lopofemusun.pbworks.com/w/file/fetch/144497676/cara_download_hello_neighbor_hide_and_seek_android_apk.pdf
    • http://zixawedeg.pbworks.com/w/file/fetch/144644427/gesowivepisanosidi.pdf
    • http://molitutolu.pbworks.com/w/file/fetch/144553944/lego_batman_movie_game_mod_apk.pdf
    • https://uploads.strikinglycdn.com/files/18fa1859-1960-4c94-bcb3-7175718a5b94/what_are_victoria_covid_restrictions.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000118b6.bin
75d5dd9ca4c8b65440daded47cd91bc3cd8b769b8d227826c271b3d2768a8e40
pdf-font-stream PDF embedded font (sfnt) at offset 0x118B6 5556 bytes
font_01_sfnt_off00012bb1.bin
a252d7ade24a1ce52bee18a03418c20c9653df4e2db9c865b305a1e0b08a1208
pdf-font-stream PDF embedded font (sfnt) at offset 0x12BB1 11900 bytes