Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc1cf22f65c57cc8…

MALICIOUS

PDF

48.3 KB Created: 2020-08-30 12:25:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f38b3743dec58a2d29e4fcacffdf8212 SHA-1: e4eb711c5a281e81e7ce3f2fe2cc41e21a68564c SHA-256: dc1cf22f65c57cc8c6b1b93cb5fdee9193d62e3be980a6e3c8bf30fad9b85e75
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged as malicious by a machine learning classifier and contains a large number of embedded links, including one pointing to a known malicious redirector. The document body, though heavily obfuscated, contains references to URLs that are likely part of a link farm designed to improve search engine rankings for malicious content. This suggests the document's primary purpose is to lure users to malicious sites.

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/wix?keyword=hindi+varnamala+and+pronunciation
    • https://cdn.shopify.com/s/files/1/0430/7963/1001/files/55221247649.pdf
    • https://cdn.shopify.com/s/files/1/0428/1414/4675/files/85500854874.pdf
    • https://cdn.shopify.com/s/files/1/0435/3500/7893/files/xikodezupor.pdf
    • https://cdn.shopify.com/s/files/1/0440/2737/9877/files/biotechnological_products.pdf
    • https://static.usrfiles.com/ugd/b8c837_c1b09fe3458b4864bedc3aacab44d508.pdf
    • https://static.usrfiles.com/ugd/b8c837_0e07668e1ce740638d2bf153e34a7753.pdf
    • https://static.usrfiles.com/ugd/b8c837_4fafe1556de04878b0877aa3f90d2071.pdf
    • https://static.usrfiles.com/ugd/b8c837_fd1238f0b46d4037a71f11897567eaff.pdf
    • https://static.usrfiles.com/ugd/fe83c3_70e9b444909b4fc3b60cd112f1dc9205.pdf
    • https://static.usrfiles.com/ugd/e1c37d_75810b5e098d42edb271deea2a31c631.pdf
    • https://cdn.shopify.com/s/files/1/0429/6045/3785/files/tefoseximimamamulobibewa.pdf
    • https://cdn.shopify.com/s/files/1/0463/3034/7675/files/academic_vocabulary_exercises.pdf
    • https://cdn.shopify.com/s/files/1/0434/8795/3053/files/totukufalat.pdf
    • https://cdn.shopify.com/s/files/1/0433/6871/0309/files/70119891752.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/

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006767.bin
7b85760889c7c9b39f5c9872d0f3e826345c0c9fb10e20fe49754339ec29c084
pdf-font-stream PDF embedded font (sfnt) at offset 0x6767 5064 bytes
font_01_sfnt_off0000787d.bin
6a3533d86737e1f9909046a412f08ccfd1dcbcede905c89f29f208619fec2f3a
pdf-font-stream PDF embedded font (sfnt) at offset 0x787D 12988 bytes
font_02_sfnt_off0000a124.bin
329430957056f10c7aec75a3e964e6894accee971806966473d649852d44d021
pdf-font-stream PDF embedded font (sfnt) at offset 0xA124 5112 bytes