Malicious PDF — malware analysis report

Static analysis result for SHA-256 2ef5e1fb1a834d76…

MALICIOUS

PDF

36.3 KB Created: 2020-08-30 01:57:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e42c0ccf0a5cd5d8f55f41a4de5982f5 SHA-1: 777ef50860e92715e9be58a093c5241676a902b1 SHA-256: 2ef5e1fb1a834d76e4eb939ce3481fb667a35b8d78de63e06bd7a0f7dba03860
154 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 a link farm hosted on static.usrfiles.com, and one critical link to a known malicious redirector at ttraff.ru. The document body, while heavily obfuscated, contains the target URL, suggesting the primary purpose is to redirect the user to malicious infrastructure. The ML classifier strongly supports the malicious nature of this PDF.

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=macbeth+act+5+questions+and+answers
    • https://cdn.shopify.com/s/files/1/0465/5330/1142/files/mubodenewosojitogusa.pdf
    • https://cdn.shopify.com/s/files/1/0435/2511/1972/files/fokukow.pdf
    • https://cdn.shopify.com/s/files/1/0431/3546/7669/files/11885748780.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/xanixiki.pdf
    • https://static.usrfiles.com/ugd/e3c460_823370f2123845eb8dc017ef67cf047d.pdf
    • https://static.usrfiles.com/ugd/d2cc1f_f721aa6745c24e6492722d46f1e03b42.pdf
    • https://static.usrfiles.com/ugd/c63dba_2048dec00db84d6bb08ede32d2d782b8.pdf
    • https://static.usrfiles.com/ugd/e745be_45ff5c4a91a84cb7b6557e1f10557a35.pdf
    • https://static.usrfiles.com/ugd/de3d83_5a9f2c446bbe4099bec4eff346688cb6.pdf
    • https://static.usrfiles.com/ugd/09c3c7_e7aa762bd44b4723a77db2a1995a98b5.pdf
    • https://static.usrfiles.com/ugd/b8c837_61a8fd9d557f4068bb5e783080b20db6.pdf
    • https://static.usrfiles.com/ugd/b8c837_9589c71ba4a94a61961b9f4a1185791f.pdf
    • https://static.usrfiles.com/ugd/b8c837_0d0110ccc70e491da8c19d887a9b0a4b.pdf
    • https://static.usrfiles.com/ugd/e643da_0cc7a822c01e4adfa1e737a9cbdd8036.pdf
    • https://static.usrfiles.com/ugd/b8c837_f034b80f0d474d84949620da31371891.pdf
    • https://static.usrfiles.com/ugd/b8c837_451c69a7ab8d4a5fa28f1bf65de6d96e.pdf
    • https://static.usrfiles.com/ugd/b8c837_41c7eab4ce414a78804d6f99c1bdfc73.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_off0000517c.bin
7ee86efd3f8b58e4099aff51821ca5e611f91022dcfca10c4e84846282df0d94
pdf-font-stream PDF embedded font (sfnt) at offset 0x517C 5484 bytes
font_01_sfnt_off00006424.bin
f3c985a51c0fcb2a5c1d58f4ac626e4529788a649713869dd9f59c1e5fa09082
pdf-font-stream PDF embedded font (sfnt) at offset 0x6424 9480 bytes