Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb7b20d1dcedd4b6…

MALICIOUS

PDF

82.9 KB Created: 2021-03-27 18:33:43 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 78e468c256ef3f15e7c733288485ab25 SHA-1: cae653e54d8426051f9783a6344cc3fa3cb35abf SHA-256: fb7b20d1dcedd4b694bb5cd9a0c1b8e79e73f9674ef320a036a9b0ab81e906ca
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to distribute malicious content or phish users. The 'ML_NYX_PDF_MALICIOUS' and 'CLAMAV_DETECTION' heuristics strongly indicate malicious intent, with ClamAV identifying it as 'Pdf.Phishing.Trojan'. The document body, though heavily obfuscated, contains references to 'firmware upgrade' and 'wkhtmltopdf', likely serving as a lure to encourage clicks on the embedded malicious URLs.

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://vilenefex.ru/strik?utm_term=perc+h700+firmware+upgrade PDF link annotation
    • https://morogixifidogaj.weebly.com/uploads/1/3/4/4/134497599/f6ba22b.pdfIn PDF document text
    • http://zdorovienashevse.xyz/4320649192241gg.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443362/normal_6039e1b83f9a9.pdfIn PDF document text
    • https://lomojibopizan.weebly.com/uploads/1/3/4/8/134886372/pafadezixakesup.pdfIn PDF document text
    • http://trysoda.club/56777532605kydd4.pdfIn PDF document text
    • http://endi-itali.space/venom_wallpaper_4kdjufj.pdfIn PDF document text
    • http://christmas-gift.ru/buludulojovekaglxc8.pdfIn PDF document text
    • https://wugedelujexot.weebly.com/uploads/1/3/1/4/131456191/fexatimepore-pinetulegepuvu-kupulufipigu.pdfIn PDF document text
    • http://clubstore.info/donde_estudiar_marketing_digital_en_lima_peruztf24.pdfIn PDF document text
    • https://cdn.sqhk.co/jekenilegefe/BzWhcif/live_sports_hd_tv_pc.pdfIn PDF document text
    • https://rozomibevepozif.weebly.com/uploads/1/3/0/7/130775668/xamasexoxun_bazogelumobemi_gisupemuje.pdfIn PDF document text
    • https://lepovomika.weebly.com/uploads/1/3/4/7/134701686/4099091.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446151/normal_6016c2e769374.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365536/normal_603cb701de6f3.pdfIn PDF document text
    • https://cdn.sqhk.co/nukebomevobe/hjlih9A/77612713584.pdfIn PDF document text
    • https://tosoremekik.weebly.com/uploads/1/3/4/7/134771766/45500.pdfIn PDF document text
    • https://tolibalib.weebly.com/uploads/1/3/4/7/134714968/8724882.pdfIn PDF document text
    • https://cdn.sqhk.co/nedupugifuka/OhgKEwc/dufidu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vaxaguv.rf.gd/is_it_legal_to_play_online_poker_in_new_york.pdfIn PDF document text
    • http://genosumexeser.epizy.com/mds_3.0_training_online.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_off00010388.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10388 5676 bytes
SHA-256: 8cd229a462411e10eb408f562c8ba2cce0883b45e1ff4d7d500cf08eb5118a31
font_01_sfnt_off000116c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116C5 11556 bytes
SHA-256: 8eddb2e24517152367011241b60171f9067307bc3f6e038ac4942fef11af8ee5