Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb4e808ad6982823…

MALICIOUS

PDF

34.3 KB Created: 2020-08-18 15:52:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f26bdf89a5db04be4bf338c9c77f3e53 SHA-1: 591d9291f8599100c4ed44d93eb53e69bdab5232 SHA-256: cb4e808ad698282306380e6f0b10a73655484fd9dc01f544ad0abd04f5d6af90
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one critical heuristic identifying a link to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains text suggesting a lure for a book download, which aligns with the observed malicious link. The ML classifier also strongly indicated maliciousness. The primary attack vector appears to be social engineering via a deceptive link.

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/pify?keyword=after+series+book+2+pdf+free
    • http://womogibip.neuroasl.com/uploads/1/3/0/7/130775129/poxarisubepud_puzoxolusitoti.pdf
    • http://duxotisel.noboundariesdm.com/uploads/1/3/0/9/130969742/f7d365.pdf
    • http://lolilu.dorewoodwi.com/uploads/1/3/2/7/132710797/8222353.pdf
    • https://cdn.shopify.com/s/files/1/0434/6871/8242/files/webabapem.pdf
    • https://cdn.shopify.com/s/files/1/0450/2824/5654/files/53856676343.pdf
    • https://cdn.shopify.com/s/files/1/0448/4068/1633/files/63844696800.pdf
    • https://cdn.shopify.com/s/files/1/0430/0318/3258/files/67568287352.pdf
    • https://cdn.shopify.com/s/files/1/0432/6889/8966/files/53481351676.pdf
    • https://cdn.shopify.com/s/files/1/0428/7827/1641/files/tarobekivakizisugago.pdf
    • https://cdn.shopify.com/s/files/1/0432/3485/3021/files/19175698670.pdf
    • https://cdn.shopify.com/s/files/1/0434/6390/1336/files/1328279522.pdf
    • https://cdn.shopify.com/s/files/1/0436/3078/8758/files/sindrome_adiposo_genital.pdf
    • https://cdn.shopify.com/s/files/1/0430/6976/7842/files/83048952495.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000460f.bin
35a2e5f84051890603cf5abc8ea3ca5f0540f64b8be029c040fc02a9b895804f
pdf-font-stream PDF embedded font (sfnt) at offset 0x460F 5120 bytes
font_01_sfnt_off00005786.bin
1363836e81394c7a79b728a2b83b2be5016d95ac4c483a1d9a24aedc11ee7afe
pdf-font-stream PDF embedded font (sfnt) at offset 0x5786 12916 bytes