Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b591bc61d7994da…

MALICIOUS

PDF

40.2 KB Created: 2020-08-15 07:30:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0ec420a39d5f7bdac09a5002f1c3a9c3 SHA-1: 2d7f02185a56276d224bf202f8d8cce98acfce25 SHA-256: 7b591bc61d7994da0747aef30c1d00322f2b37586fddf881c4b0384c7f5f6771
152 Risk Score

Malware Insights

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

The PDF contains a mass of external links, many hosted on Shopify, designed to appear as legitimate documents. One of these links, https://ttraff.ru/wb?keyword=workforce%20planning%20tools%20pdf, is identified as a malicious redirector. The ML classifier strongly indicates maliciousness, and the document body, though obfuscated, contains references to the redirector URL and other PDF 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/wb?keyword=workforce%20planning%20tools%20pdf
    • http://jafadaj.riversturnpress.com/uploads/1/3/0/8/130814347/69361d0e.pdf
    • http://wirexut.finleydesignart.com/uploads/1/3/2/7/132740214/b03d793349.pdf
    • http://files.ilovequebeccity.com/uploads/1/3/1/3/131383977/9219a.pdf
    • http://fabuworub.the309s.com/uploads/1/3/0/7/130739919/19e0a111dd6e.pdf
    • https://cdn.shopify.com/s/files/1/0435/7675/4344/files/suruxefowuneperip.pdf
    • https://cdn.shopify.com/s/files/1/0438/8379/0491/files/kuvexokolum.pdf
    • https://cdn.shopify.com/s/files/1/0437/7811/3697/files/proposed_school_calendar_2020.pdf
    • https://cdn.shopify.com/s/files/1/0427/7128/4135/files/zidofakavilezikikopebazid.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/63529720688.pdf
    • https://cdn.shopify.com/s/files/1/0436/3943/9510/files/76821950567.pdf
    • https://cdn.shopify.com/s/files/1/0427/5542/4423/files/examen_auxiliar_administrativo_comunidad_de_madrid.pdf
    • https://cdn.shopify.com/s/files/1/0433/7215/0947/files/the_air_he_breathes_brittainy_c._cherry.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_off00005f8a.bin
f51362968bfa2c20b9eaa9144ad3f115539e38655625985df88c0dad126bbcf7
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F8A 5400 bytes
font_01_sfnt_off00007208.bin
3c769d165c7e0d8388b26b76e4a753387d7c7d5d9a791c2537d75822758c740a
pdf-font-stream PDF embedded font (sfnt) at offset 0x7208 9992 bytes