Malicious PDF — malware analysis report

Static analysis result for SHA-256 720cc7f7809174e2…

MALICIOUS

PDF

77.8 KB Created: 2021-03-12 07:27:09 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-04
MD5: ff2051ece65a820761ff53d01f2a4f27 SHA-1: e260e27727425c1ea935813dc4f26ffd5b579bd7 SHA-256: 720cc7f7809174e2ae12158d8f316f229d4eaaba40d7fe1c310b61ba5dd8fe79
244 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spamming operation. One of the embedded URLs, https://crophysi.ru/strik?utm_term=why+do+stars+appear+to+move+along+arcs+in+the+night+sky, is identified as a malicious redirector. The ML classifier and ClamAV detection further support its malicious nature, likely serving as a lure to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • 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://crophysi.ru/strik?utm_term=why+do+stars+appear+to+move+along+arcs+in+the+night+sky In PDF document text
    • https://static.s123-cdn-static.com/uploads/4373297/normal_5fe19da90d85b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464083/normal_604ad269acdef.pdfIn PDF document text
    • https://cdn.sqhk.co/xibetevoxaj/jb8Cija/80668965281.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4477373/normal_5ff558383f5e6.pdfIn PDF document text
    • https://cdn.sqhk.co/nosilaxuziz/nbjhogi/antiyoy_level_90.pdfIn PDF document text
    • https://cdn.sqhk.co/zejizoguzut/Mfiaegi/millionaire_trading_mom_1k_club_reviews.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449395/normal_602de728e790a.pdfIn PDF document text
    • https://mabamigetope.weebly.com/uploads/1/3/4/4/134493328/bojamojemudi_jizusuvetoponer_bujifibetififa_bevor.pdfIn PDF document text
    • https://cdn.sqhk.co/furugilenu/jez7ija/wish_coupons_for_existing_customers_october_2019.pdfIn PDF document text
    • https://cdn.sqhk.co/mikevoponage/icLjaHZ/notification_sound_not_working_android_tablet.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469831/normal_6037b4b2ccf8d.pdfIn PDF document text
    • https://zefopezonokav.weebly.com/uploads/1/3/1/3/131398054/sirun_bivixiwadod_sagavanaxogu.pdfIn PDF document text
    • https://cdn.sqhk.co/tevimuwijile/hghcNif/gardenscapes_levels_2020.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4382186/normal_5fdeea61d456f.pdfIn PDF document text
    • https://cdn.sqhk.co/dibidoretu/eiyCggv/93924835965.pdfIn PDF document text
    • https://lakojelot.weebly.com/uploads/1/3/1/6/131637836/tigojojugifewa-sujetume-xavopina-ropemezorono.pdfIn PDF document text
    • https://lisebilapuwuw.weebly.com/uploads/1/3/4/0/134096741/5844444.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478688/normal_600c6f4996c79.pdfIn PDF document text
    • https://cdn.sqhk.co/lilaxikixo/eifHgg1/leselatapofevojupiwidedeb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367297/normal_6039d81cea634.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4401971/normal_5fff7e6836a27.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/feliso/ask_the_dust_movie_download_in_hindi.pdfIn PDF document text
    • https://s3.amazonaws.com/webipejonavuv/crossbill_guides_andalucia.pdfIn PDF document text
    • https://s3.amazonaws.com/bogeguva/gupinelan.pdfIn PDF document text
    • https://s3.amazonaws.com/jowutoneranemuk/helping_and_linking_verbs.pdfIn PDF document text
    • https://s3.amazonaws.com/tunenijexe/beethoven_symphony_5_piano.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_off0000f1da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1DA 5724 bytes
SHA-256: 9834e0f9bb4d7e6144b7c94d0486f98cb6e418310a46a15ccbda5422796b021f
font_01_sfnt_off00010548.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10548 10364 bytes
SHA-256: 7610dc58aa5415bbb08456ac7d2b8efcb8e62a0e2b3ad3972a7774a81ce8b45e