Malicious PDF — malware analysis report

Static analysis result for SHA-256 f86f526b463136c0…

MALICIOUS

PDF

52.1 KB Created: 2020-08-02 22:44:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d89d2c160959f55847e0a5a87af8b92a SHA-1: 55a4612b0bd7d4a85a508ad15e6d33cd751d7acb SHA-256: f86f526b463136c034fbb270e6588851f52122c2beeb7d66e12d5921e0b36fa8
152 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded links, with one identified as a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains the URL that triggered the malicious redirector heuristic. The presence of numerous external PDF links suggests an attempt at SEO manipulation or a link farm to distribute malicious 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.cc/pify?keyword=height+of+a+binary+search+tree
    • http://files.whiskeycreekranches.com/uploads/1/3/2/6/132681210/sekunapad_femol.pdf
    • http://files.ricasbrainstormroom.com/uploads/1/3/0/7/130739369/wetegiwalijuvupomexi.pdf
    • http://files.ms158qmusic.com/uploads/1/3/1/4/131453455/wotinoj-riforufakibiza-koxivefunofag.pdf
    • https://cdn.shopify.com/s/files/1/0438/8143/1195/files/39687451266.pdf
    • https://cdn.shopify.com/s/files/1/0429/2640/7843/files/30696440172.pdf
    • https://cdn.shopify.com/s/files/1/0429/5943/7975/files/fadimulivodem.pdf
    • https://cdn.shopify.com/s/files/1/0432/9907/8299/files/fupulobes.pdf
    • https://cdn.shopify.com/s/files/1/0440/6951/9510/files/milavowaporogiketutirax.pdf
    • https://cdn.shopify.com/s/files/1/0436/8770/6774/files/9926253996.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/6338597663.pdf
    • https://cdn.shopify.com/s/files/1/0433/8126/0438/files/15876209468.pdf
    • https://cdn.shopify.com/s/files/1/0429/4764/1510/files/wowemesevolunuwa.pdf
    • https://cdn.shopify.com/s/files/1/0432/1030/9787/files/88355580494.pdf
    • https://cdn.shopify.com/s/files/1/0428/9688/3868/files/tubigi.pdf
    • https://cdn.shopify.com/s/files/1/0435/6915/2163/files/javascript_iterate_over_object.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_off00008e6c.bin
50fff2b9cf73bfc64d6fb6d03697efbce5091f6ef30f272c082017d404fb7e49
pdf-font-stream PDF embedded font (sfnt) at offset 0x8E6C 5312 bytes
font_01_sfnt_off0000a08b.bin
56b1ba8fa0c58a13675d855157a471f283c0c053fed08edac68ca1687489e259
pdf-font-stream PDF embedded font (sfnt) at offset 0xA08B 10308 bytes