Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbe98c712246f008…

MALICIOUS

PDF

42.4 KB Created: 2020-08-31 12:01:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 31a444f09357cb8e0bd984ee1f6d0b13 SHA-1: 62c95998c9239094d59ef2b5de0cbd1fd465a2d4 SHA-256: fbe98c712246f0083fdbd856a0c668209b2f2506b102be760d3d6d828c844367
152 Risk Score

Malware Insights

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

The PDF document was flagged as malicious by a machine learning classifier and contains a critical heuristic indicating it links to known malicious redirector infrastructure. It also exhibits characteristics of a PDF link farm, with numerous embedded URLs pointing to external PDF files, likely for SEO manipulation or to distribute further malicious content. The primary malicious IOC is the redirector URL.

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=reading+comprehension+difficult+leve
    • https://cdn.shopify.com/s/files/1/0431/4460/9943/files/lisejiwotatumoxewezov.pdf
    • https://cdn.shopify.com/s/files/1/0428/6955/5356/files/40411567029.pdf
    • https://cdn.shopify.com/s/files/1/0433/5730/7039/files/dugatego.pdf
    • https://static.usrfiles.com/ugd/69b86f_934996356eb34d0d9946f85e8c5fdbe4.pdf
    • https://static.usrfiles.com/ugd/4bdc6d_8eec35a778004082a841f6fae6d3f8d6.pdf
    • https://static.usrfiles.com/ugd/5ad03d_8fb8b571b7d54b0c8a9f0a3a50e86806.pdf
    • https://static.usrfiles.com/ugd/b8c837_5b2e3296347541adbc8f1a04cf718a93.pdf
    • https://static.usrfiles.com/ugd/b8c837_909093583bfc4f7880e0198000c6c45a.pdf
    • https://static.usrfiles.com/ugd/b8c837_fe8aeb1f89ed49f4afa2aec51ad6f582.pdf
    • https://static.usrfiles.com/ugd/538d67_af7ee5c31b564375ad3e899e376deaaf.pdf
    • https://cdn.shopify.com/s/files/1/0428/7810/7811/files/vowobajebazedala.pdf
    • https://cdn.shopify.com/s/files/1/0431/7767/2868/files/34473382610.pdf
    • https://cdn.shopify.com/s/files/1/0429/4616/6943/files/neoplasia_chapter.pdf
    • https://cdn.shopify.com/s/files/1/0436/1843/5229/files/free_calendar_template_january_2019.pdf
    • https://cdn.shopify.com/s/files/1/0461/1345/6291/files/68154844584.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_off00006635.bin
676654fc61416623bd8af62fdfcaec1498ff6c62ae8341766b12dea12bd691e9
pdf-font-stream PDF embedded font (sfnt) at offset 0x6635 5636 bytes
font_01_sfnt_off0000793b.bin
560510220ab209fef75478b2233763ee9bfd610693a28adad633d468db4f58a3
pdf-font-stream PDF embedded font (sfnt) at offset 0x793B 10368 bytes