Malicious PDF — malware analysis report

Static analysis result for SHA-256 b26c37656dcc0c83…

MALICIOUS

PDF

41.0 KB Created: 2020-08-13 23:12:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-09
MD5: d0ece701ab7769656ed72d4fbfb540fa SHA-1: 4098247858f170659e9d6541ad4add676c6943cd SHA-256: b26c37656dcc0c83cd4fb20a438ba29ff5b879484ea9f127a24f6d103868761d
202 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to a redirector service (ttraff.ru) disguised as a manual for 'Bk precision 2120b oscilloscope'. This suggests an SEO-based link farm or phishing attempt to drive traffic to malicious infrastructure. The ML classifier also strongly indicated maliciousness. No scripts were extracted, but the PDF structure itself facilitates the malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • 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.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://ttraff.ru/wb?keyword=bk%20precision%202120b%20oscilloscope%20manual In PDF document text
    • http://files.surfcoastarts.com/uploads/1/3/1/4/131454850/tovuxukedilijin.pdfIn PDF document text
    • http://molovor.embodimentcollective.co.nz/uploads/1/3/0/7/130775164/kepelisufafokewimo.pdfIn PDF document text
    • http://vojevufof.astrobrandmedia.com/uploads/1/3/1/8/131871991/nuzazesenej.pdfIn PDF document text
    • http://xidilo.kcrkradio.com/uploads/1/3/0/7/130776688/d57b9ccacd55f.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://cdn.shopify.com/s/files/1/0428/0467/4727/files/adverb_clauses_exercises_with_answers.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/3427/2163/files/56414743811.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0455/4902/7493/files/entrepreneurial_skills.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/2066/5510/files/stihl_ms180c_repair_manual.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0438/7779/3960/files/20090712534.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/7003/7917/files/84735207135.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/4807/4405/files/xifabijozuxuga.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/9985/7823/files/calculus_and_vectors_12_mcgraw_hill_ryerson_chapter_4.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0436/9793/0393/files/mgsu_bsc_1st_year_syllabus_2020.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/4848/5535/files/zonojosevamuxedawam.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000052af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x52AF 5460 bytes
SHA-256: 7a7cd534545352ee13e6596ac70ab888a7c9ab3394b6d7efce6dee7191231412
font_01_sfnt_off0000651f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x651F 10532 bytes
SHA-256: 4fcdfc2f0c964f8dacab64c9fdd8a09a5c612bb91220553c83c26de82ea07212
font_02_sfnt_off0000890b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x890B 4324 bytes
SHA-256: 781b9fae2fb9201b4a05d2041fea553bb2973f1d011ab9c51e3326c72e342c60