Malicious PDF — malware analysis report

Static analysis result for SHA-256 185c02e6bce0635e…

MALICIOUS

PDF

40.5 KB Created: 2020-08-01 20:03:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ca8bbcb60b4233fe42a391d51900414b SHA-1: a64e893e98023a2972ae68518ce1ed1d0ec6c0d3 SHA-256: 185c02e6bce0635ea4b4468738b19151d44ceeaec32858565854d1738cb3c07e
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to suspicious or malicious redirector infrastructure. The ML classifier strongly indicated maliciousness, and the presence of a known malicious redirector URL reinforces this. The document body, though heavily obfuscated, contains text related to worksheets and URLs, suggesting a lure to external content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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=subtracting%203%20digit%20numbers%20worksheet%20pdf
    • http://files.khuloudkonsultancy.com/uploads/1/3/0/7/130775712/c7b2f501358a.pdf
    • http://files.thomasrupertcharliebeal.com/uploads/1/3/1/1/131164573/b97df76a88b8.pdf
    • http://files.stickemupracks.ca/uploads/1/3/1/1/131163867/gotunugodise_dubewawaloxav.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/2342/5955/files/mimop.pdf
    • https://cdn.shopify.com/s/files/1/0428/3518/1724/files/16618930163.pdf
    • https://cdn.shopify.com/s/files/1/0429/7264/3491/files/napujeguwuka.pdf
    • https://cdn.shopify.com/s/files/1/0434/4017/7317/files/domorazigo.pdf
    • https://cdn.shopify.com/s/files/1/0434/5223/5938/files/66941711491.pdf
    • https://cdn.shopify.com/s/files/1/0438/7805/6091/files/66336373450.pdf
    • https://cdn.shopify.com/s/files/1/0434/0485/3406/files/8285518587.pdf
    • https://cdn.shopify.com/s/files/1/0434/7173/2889/files/72884751888.pdf
    • https://cdn.shopify.com/s/files/1/0429/2398/3001/files/lawesilubu.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/84770620138.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/86477918810.pdf
    • https://cdn.shopify.com/s/files/1/0433/9938/1157/files/77936714362.pdf
    • https://cdn.shopify.com/s/files/1/0430/7258/5888/files/90163412911.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005ed8.bin
6f0aca57e988dcc716d0f82ee923cd586659cb98b7dad2f890a236acf729ee80
pdf-font-stream PDF embedded font (sfnt) at offset 0x5ED8 6100 bytes
font_01_sfnt_off0000737a.bin
838a57b5f2ee1b64856d6e90e0ffbb820cd4c29fc73c4c9c3681a3ee27113f1a
pdf-font-stream PDF embedded font (sfnt) at offset 0x737A 9772 bytes