Malicious PDF — malware analysis report

Static analysis result for SHA-256 e173a2a133a083f8…

MALICIOUS

PDF

45.5 KB Created: 2020-08-05 22:45:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 28072ca65fe71c308c7ffce55826c274 SHA-1: a3b8c5615cfae8e95a5beb21826f660f939916bb SHA-256: e173a2a133a083f8671401cfe83237fd2e17fd6747b62ad8343564a1d7d9fc3f
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.ru, which is designed to lure users to a malicious site. The document body, though heavily obfuscated, contains the same URL and appears to be a lure for learning German. The PDF also contains a large number of links to other PDFs hosted on Shopify, likely for SEO manipulation to increase visibility. The ML classifier strongly indicated maliciousness.

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=libro+aprender+aleman+en+7+dias+pdf
    • http://kavigak.mivestido.net/uploads/1/3/1/3/131381078/jimanod.pdf
    • http://files.stackhousepark.com/uploads/1/3/0/7/130776409/2668435.pdf
    • http://files.williamreimann.com/uploads/1/3/1/4/131453054/sebagazejeto.pdf
    • http://files.leonardpaul.com/uploads/1/3/1/4/131406659/zufibalufuvo-wuzime-lunegitudinije-vokisevoduxaro.pdf
    • https://cdn.shopify.com/s/files/1/0447/8484/4949/files/mystring_class_c.pdf
    • https://cdn.shopify.com/s/files/1/0429/4865/7311/files/97283814586.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/riwemabosemuridaredexe.pdf
    • https://cdn.shopify.com/s/files/1/0432/0913/0143/files/athens_airport_terminal_map.pdf
    • https://cdn.shopify.com/s/files/1/0436/2846/2240/files/medum.pdf
    • https://cdn.shopify.com/s/files/1/0439/6626/7550/files/electrical_aptitude_test.pdf
    • https://cdn.shopify.com/s/files/1/0430/3169/1421/files/toledo_police_accident_reports.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/90840236881.pdf
    • https://cdn.shopify.com/s/files/1/0432/8669/1998/files/bedutonexebod.pdf
    • https://cdn.shopify.com/s/files/1/0434/5344/8358/files/32663688753.pdf
    • https://cdn.shopify.com/s/files/1/0434/4784/5030/files/persuasive_writing_rubric.pdf
    • https://cdn.shopify.com/s/files/1/0435/4883/6004/files/94020328862.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_off000070ad.bin
9b9e19f9122e246e3c275af7ae74cd98a70a51cf1b465016156929b184ef674c
pdf-font-stream PDF embedded font (sfnt) at offset 0x70AD 5348 bytes
font_01_sfnt_off000082ca.bin
e18af7735bd0fc4603f991ca46fe58fe8e7583040f13d3d6edbd1f10cf16415e
pdf-font-stream PDF embedded font (sfnt) at offset 0x82CA 11372 bytes