Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a9e81c5046fde31…

MALICIOUS

PDF

40.5 KB Created: 2020-08-06 23:18:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-08
MD5: 5ec3c901e42d7e862d3346c9688859f3 SHA-1: a430a536833c94d1c2ddb51c051bf35a10b96edd SHA-256: 0a9e81c5046fde31e895577bb5263263dfd3e793504f560bc8cf327b442fcfb9
202 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many pointing to a redirector service (ttraff.ru) that is associated with malicious activity. The document body and heuristics indicate a lure related to PDF conversion, likely a phishing or scam attempt. The ML classifier strongly suggests maliciousness, and the presence of a link farm further supports a malicious intent to direct users to potentially harmful sites.

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=converting%20pdf%20to%20editable%20word%20document%20with%20adobe In PDF document text
    • http://files.stealthbrew.co/uploads/1/3/2/6/132681665/vifuwegozetaze-jedew-kiresab.pdfIn PDF document text
    • http://luzenak.nmffa.org/uploads/1/3/1/6/131606289/1358809.pdfIn PDF document text
    • http://files.paintersincentrallondon.co.uk/uploads/1/3/0/7/130775808/686f78af7a77.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/5934/6582/files/green_building_design_thesis.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/tipibag.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/41758367329.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0439/0574/5051/files/riluxejo.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/6674/4214/files/tugugazopiwizesokej.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/58933331969.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/6954/6395/files/lamiludewanasilaluvuxofe.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/2450/6266/files/93162038298.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0440/1571/4469/files/wuruzusezawigexevivatawa.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0435/5797/8273/files/nibafeje.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/3293/6605/files/ketifarurap.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/1373/4563/files/24231960370.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/2073/7950/files/56691187355.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
🗂 Part of campaign: stealthbrew.co 3 samples

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005f97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5F97 5588 bytes
SHA-256: d4b560fe118966062cd507ebeffc84916517cf0d484a38d9c55ba623ca9197ac
font_01_sfnt_off00007282.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7282 10080 bytes
SHA-256: 53914894d0baa48b78c72d59773eb8056a98e1e6ce4ae1c1947188ddd78425e4