Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7af79a0812a796c…

MALICIOUS

PDF

35.4 KB Created: 2020-08-21 20:07:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f00a949720f763f3e67b8b8ceb25b8b1 SHA-1: 29629c14aa9bfbd3726318a2b7b89dc69acaa85b SHA-256: e7af79a0812a796c2d9af9a93183308cc9aaaa05a588cbdbae094469c6c06040
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to Shopify domains hosting other PDFs, forming a link farm. One critical heuristic identified a link to a known malicious redirector, ttraff.ru, which is likely the primary malicious payload delivery mechanism. The document body, though heavily obfuscated, contains keywords related to job searching, suggesting a lure to trick users into clicking the malicious links.

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=aramark+uniforms+jobs
    • http://files.triadsbesthvac.com/uploads/1/3/0/7/130740429/e6ffc21eed.pdf
    • http://files.creditriskanalytics.net/uploads/1/3/0/8/130874370/nuzozenol_nebiterefom.pdf
    • http://files.clearpathemployer.com/uploads/1/3/1/3/131383544/01eb14ca502.pdf
    • https://cdn.shopify.com/s/files/1/0438/0796/5345/files/marginal_of_bivariate_normal_distribution.pdf
    • https://cdn.shopify.com/s/files/1/0432/8715/0752/files/busawavaxoririgubon.pdf
    • https://cdn.shopify.com/s/files/1/0431/2226/2178/files/1329821691.pdf
    • https://cdn.shopify.com/s/files/1/0435/5624/1557/files/38649155325.pdf
    • https://cdn.shopify.com/s/files/1/0430/5344/9367/files/jio_store_whatsapp_app_jio_phone.pdf
    • https://cdn.shopify.com/s/files/1/0428/8974/0441/files/43574306150.pdf
    • https://cdn.shopify.com/s/files/1/0432/9324/5590/files/26093033523.pdf
    • https://cdn.shopify.com/s/files/1/0436/4979/4213/files/73286316017.pdf
    • https://cdn.shopify.com/s/files/1/0435/9569/4239/files/20682572959.pdf
    • https://cdn.shopify.com/s/files/1/0430/9994/7169/files/nezag.pdf
    • https://cdn.shopify.com/s/files/1/0427/7764/1116/files/61405163578.pdf
    • https://cdn.shopify.com/s/files/1/0431/3684/3933/files/6138392178.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_off00004dd8.bin
53f7579022e61f7210f8ff25d54ed0d866496fb25dfa329727543f0fd13331c5
pdf-font-stream PDF embedded font (sfnt) at offset 0x4DD8 5152 bytes
font_01_sfnt_off00005f48.bin
de6acf12672ae5e0eb8a831f45968045239ca6aef34e5faf920b8d2b518f8c84
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F48 9888 bytes