Malicious PDF — malware analysis report

Static analysis result for SHA-256 81b41a953a2e58c3…

MALICIOUS

PDF

57.7 KB Created: 2020-08-09 16:12:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-07
MD5: 0353671b3bee1bbe7e536be793a4d579 SHA-1: eb6643ef4824178685dda4eaa425eab8f3f998cc SHA-256: 81b41a953a2e58c31e5ecdde3a1a3a94daee3e8279b2afd1146286700b21a2e7
202 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to a redirector service (ttraff.com), which is flagged as malicious. The document body, though heavily obfuscated, contains a URL that appears to be the primary lure. The presence of a 'download button' heuristic and the ML classifier's high confidence score further support a malicious intent, likely to redirect users to a phishing or malware distribution site.

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.com/pify?keyword=cateterismo+vesical+masculino+pdf In PDF document text
    • http://files.conoverghosts.com/uploads/1/3/1/3/131398184/550f3.pdfIn PDF document text
    • http://files.bookworksbyday.com/uploads/1/3/1/4/131453588/jiluxarujin_rebuf_rizirejekafubeb.pdfIn PDF document text
    • http://files.dahammaak2k.com/uploads/1/3/1/4/131409442/237179.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/1/0432/7620/6238/files/31911503399.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/8865/0135/files/demuloriwozufil.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/6520/5141/files/ludodiki.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/womosoravitixugefiwil.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/0406/0071/files/abomasal_displacement_in_cattle.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/4686/2997/files/bomekenugizoxilowuzopives.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/0156/0737/files/42485948234.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/5969/9109/files/91371887408.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/5109/0077/files/bayesian_statistics_in_r.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/9345/8070/files/92998859594.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/6559/0438/files/50419385882.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/9633/4753/files/elf_bowling_3.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/3695/8104/files/89407176433.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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn 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_off00009404.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9404 6416 bytes
SHA-256: a497fc52ef216d2369a1cda088bdeb49e1b2edea4e2999984a7939df6a238a3e
font_01_sfnt_off0000a3ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA3CE 5264 bytes
SHA-256: e82219531a92a1b06a816d8a71ed4ae3088eacb13227f513b6ed045762489f03
font_02_sfnt_off0000b5a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5A3 10376 bytes
SHA-256: 5b774adf583e1c7fbde0a058708ea31332bf79a8d90a7b19749dccca40b29914