Malicious PDF — malware analysis report

Static analysis result for SHA-256 d15d1ff3a7e1d92d…

MALICIOUS

PDF

41.5 KB Created: 2020-09-01 09:59:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f9f87117696be22cdca39faaa35a21d4 SHA-1: 67355241dd9831b2cdc8eac910c812d3858574b5 SHA-256: d15d1ff3a7e1d92dc1524a17d3e633aba7cac133e4a2f81b8798f5d28f3e69cd
152 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier as malicious and contains a critical heuristic indicating a link to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains the URL that triggered the malicious redirector heuristic. The presence of numerous other PDF links, many pointing to static.usrfiles.com, suggests a link farm or SEO poisoning attempt to drive traffic to malicious sites.

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.com/wix?keyword=hernia+de+hiato+por+deslizamiento+pdf
    • https://static.usrfiles.com/ugd/9b5f63_6e1e8030466448d6add5c21775157812.pdf
    • https://static.usrfiles.com/ugd/b8c837_b11fb9b6e82542b783bc017fea5d10af.pdf
    • https://static.usrfiles.com/ugd/e2b09b_e3489dbd95f743c7bd1ab27edefac443.pdf
    • https://static.usrfiles.com/ugd/b8c837_5a0b90329eae4c639336662e90f90bb4.pdf
    • https://static.usrfiles.com/ugd/b8c837_877177b3f2dd40348fcb65c416badf45.pdf
    • https://static.usrfiles.com/ugd/b8c837_849ea72b66b94d2296ea6375bc26e85b.pdf
    • https://static.usrfiles.com/ugd/32acb1_4d3c488f62e9418e8edbfa992adf801e.pdf
    • https://cdn.shopify.com/s/files/1/0432/0319/9138/files/xazoposiwelugelu.pdf
    • https://cdn.shopify.com/s/files/1/0431/8828/9694/files/2349066187.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/kosetomamevisired.pdf
    • https://static.usrfiles.com/ugd/f0e51d_ad59470b2e674dc3959d665ea3b0cc10.pdf
    • https://static.usrfiles.com/ugd/7c30af_ca04c002137448028c28a56bb941d482.pdf
    • https://static.usrfiles.com/ugd/b8c837_bb1c2cc5fe0c464d98a326934d4d392c.pdf
    • https://static.usrfiles.com/ugd/b8c837_5acd9ac1fd20458884f93b90043b3982.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_off00006095.bin
4c5e1950a793af434483b952fa25c6e75247f02a18e4d2bb3d2f76b9d88f6c1a
pdf-font-stream PDF embedded font (sfnt) at offset 0x6095 5292 bytes
font_01_sfnt_off0000726e.bin
1b33cfe64a35a335538ceb247508e4e5b234e5f869ec0efb6ae5146ec3170b88
pdf-font-stream PDF embedded font (sfnt) at offset 0x726E 11408 bytes