Malicious PDF — malware analysis report

Static analysis result for SHA-256 76eb386780a204b3…

MALICIOUS

PDF

37.3 KB Created: 2020-08-08 17:43:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 63603ff4cbd8a272040a993b8eb6d8d8 SHA-1: c93c75035d007c5ea83d8186eb5ebe26e56c4fcd SHA-256: 76eb386780a204b390164c89352ba6c3df0c4aae094777d9ff60c151ce6f628f
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a mass link farm, with the primary URL leading to a known malicious redirector. The document body, though obfuscated, contains the target URL and appears to be a lure for a textbook PDF. The ML classifier strongly indicated maliciousness, supporting the redirector and link farm findings.

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.com/pify?keyword=an+introduction+to+logic+irving+copi+pdf
    • http://files.calligraphicconnections.com/uploads/1/3/0/8/130814636/c357e5.pdf
    • http://files.cakeneq.com/uploads/1/3/1/3/131383775/jogidifugoxibeb.pdf
    • http://files.organicallyhers.com/uploads/1/3/1/3/131398075/zutesononadu.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/8990/3264/files/19221114353.pdf
    • https://cdn.shopify.com/s/files/1/0431/1983/7345/files/81048827674.pdf
    • https://cdn.shopify.com/s/files/1/0436/2852/7776/files/90182880364.pdf
    • https://cdn.shopify.com/s/files/1/0430/1661/8145/files/zeguxabumuber.pdf
    • https://cdn.shopify.com/s/files/1/0437/8702/6581/files/texulovivosubemupegina.pdf
    • https://cdn.shopify.com/s/files/1/0437/7418/1534/files/nmeros_primos_e_compostos.pdf
    • https://cdn.shopify.com/s/files/1/0432/0867/1394/files/savenipodupirusab.pdf
    • https://cdn.shopify.com/s/files/1/0439/4080/6824/files/dovefefonebek.pdf
    • https://cdn.shopify.com/s/files/1/0437/0428/7383/files/tiluwud.pdf
    • https://cdn.shopify.com/s/files/1/0435/3196/0474/files/madutivaki.pdf
    • https://cdn.shopify.com/s/files/1/0429/8833/9354/files/gusuw.pdf
    • https://cdn.shopify.com/s/files/1/0435/3340/2266/files/pegiba.pdf
    • https://cdn.shopify.com/s/files/1/0439/5089/9368/files/centimeter_ruler_actual_size.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_off0000543b.bin
33ea5a4a2af85c2d1c39fd18fe8ec3f494edf55780c900d9ab8b4394d1ce0be7
pdf-font-stream PDF embedded font (sfnt) at offset 0x543B 4984 bytes
font_01_sfnt_off0000654e.bin
27313c5b39e0820546fbf7e05ba4ec1598ada10aedb443e79cf4998ada68c288
pdf-font-stream PDF embedded font (sfnt) at offset 0x654E 10204 bytes