Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ae9cf6fb2ceb189…

MALICIOUS

PDF

42.1 KB Created: 2020-08-31 06:05:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 13f792ac55fe6bc56857ed277b81ee52 SHA-1: 1257eb71bd9fc4385aecc0c7b22ceb9ff9c2ffd5 SHA-256: 4ae9cf6fb2ceb189af74f7b665a6318d2eaa7b767b1e43ff0d07bafa73f1ee59
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a link to a known malicious redirector, ttraff.ru, which is likely used to obscure the final destination of the malicious payload. The document also features a large number of links to other PDFs hosted on static.usrfiles.com, suggesting a link farm or SEO poisoning attempt to increase visibility. The ML classifier strongly indicated maliciousness, supporting the presence of a malicious redirector.

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=delonghi+nabucco+coffee+maker
    • https://static.usrfiles.com/ugd/b8c837_23de9b25a7244af8b20cabae8e05d6d0.pdf
    • https://static.usrfiles.com/ugd/0a51c1_bf95a8c1d73c4fbfae2d3150ac9d8e66.pdf
    • https://static.usrfiles.com/ugd/a86d68_ad584d9852d54ef5a97889e44940a122.pdf
    • https://static.usrfiles.com/ugd/9ff9b8_56e58cec8e064e19bc359398b1697f87.pdf
    • https://cdn.shopify.com/s/files/1/0429/8443/9971/files/30272057960.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/73121007565.pdf
    • https://static.usrfiles.com/ugd/756799_1552d0bd31a24ce1a5de3e72218238d2.pdf
    • https://static.usrfiles.com/ugd/20d83a_868205fa2b4240d794c7d7c3eb26f017.pdf
    • https://static.usrfiles.com/ugd/930050_a328b9fb85c7472e9447ddad11017f65.pdf
    • https://static.usrfiles.com/ugd/ecec20_fcac7092be8d4a06a695ac29050bc338.pdf
    • https://static.usrfiles.com/ugd/b8c837_a204aadcb32040fea2a3631dabc818db.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/31670740491.pdf
    • https://cdn.shopify.com/s/files/1/0431/7295/4269/files/vafawovavijepukavixij.pdf
    • https://cdn.shopify.com/s/files/1/0429/7313/5011/files/sevenuzutarojiwagobegitem.pdf
    • https://cdn.shopify.com/s/files/1/0431/1734/6965/files/clinical_pharmacy_therapeutics_roger_walker.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_off00006664.bin
3be404998f57751c5a59ce09fbd62df87f2df1addfae9ca415eae4857e00edba
pdf-font-stream PDF embedded font (sfnt) at offset 0x6664 5320 bytes
font_01_sfnt_off00007857.bin
399af942c61ec050065d29a1c3b4d80df12abf7463f4806587f8ea3e0ae396d1
pdf-font-stream PDF embedded font (sfnt) at offset 0x7857 10176 bytes