Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9855c153c0ab308…

MALICIOUS

PDF

72.4 KB Created: 2021-05-25 05:57:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 2819db977e5339ece84e399154d7619c SHA-1: c5ba1446873300618b93b23ee29b3bc6ddf1ebd4 SHA-256: b9855c153c0ab308c6792a64df5b5a4f2aa90742cae73db9b6417117d7ca8ff7
196 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many of which point to SEO redirectors, suggesting a phishing or malware distribution campaign. The primary malicious URL identified is https://jottigo.ru/strik?utm_term=bass+guitar+book+free+download, which is likely used to redirect users to a malicious payload or phishing page.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://jottigo.ru/strik?utm_term=bass+guitar+book+free+download PDF link annotation
    • https://wotawodakel.weebly.com/uploads/1/3/5/3/135316359/tovadawoso_pifupukarebojow_gejafipitov_bufubatitadib.pdfIn PDF document text
    • https://tedowinoni.weebly.com/uploads/1/3/5/3/135304389/gurobiremupo.pdfIn PDF document text
    • https://kuxadituva.weebly.com/uploads/1/3/1/3/131380841/9547496.pdfIn PDF document text
    • https://xedukigujidazan.weebly.com/uploads/1/3/4/5/134512451/7619862.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368500/normal_60142a2a0b340.pdfIn PDF document text
    • https://giruwaferelesed.weebly.com/uploads/1/3/4/8/134850821/9125489.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404503/normal_6038d590e99bf.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4530323/normal_5fc6c6bb769ff.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450721/normal_5fcd5aca7b6a7.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/rizijubovapuk/gipebokudikifuwuwakenag.pdfIn PDF document text
    • https://s3.amazonaws.com/tujeviwakirawu/gafubokiwesuxoguguwizaji.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/17c7e239-d442-4434-97d6-0b595018cda0/hp_officejet_4630_ink_cartridge_wont_move.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c158f6a-6544-4411-8861-4556341a9166/debogulewejo.pdfIn PDF document text
    • https://s3.amazonaws.com/wefemabeni/cisco_air_lap1142n_a_k9_setup.pdfIn PDF document text
    • https://s3.amazonaws.com/migivewuwe/candle_sing_happy_birthday_video_free.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e9850564-4c22-4f47-a2a3-af639fa52f80/sukemomazewepajir.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b69aba98-71aa-448f-91ed-6656d7322d4f/67260938881.pdfIn PDF document text
    • https://s3.amazonaws.com/wewiro/local_area_connection_doesnt_have_a_valid_ip_configuration.pdfIn PDF document text
    • https://s3.amazonaws.com/gonafoziguwewe/bedusowufijazasenu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/12d081fe-5343-46c0-b4ee-a653890cb746/keto_diet_food_pictures.pdfIn PDF document text
    • https://s3.amazonaws.com/falevi/turenodigotevev.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_off0000dd66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD66 5420 bytes
SHA-256: 7b2eb0ba388e076459098b81e54c96506d5f1375ed5e25eb7c7928f438db4fa7
font_01_sfnt_off0000eff8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF8 10632 bytes
SHA-256: 6a57d982e87fa97d362054ce07ebcac2d4855cb199d71e4d6220343b80982899