Malicious PDF — malware analysis report

Static analysis result for SHA-256 558d79cfe52dc6bf…

MALICIOUS

PDF

46.4 KB Created: 2020-08-30 17:33:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cf3895e6f6ee8e81191e4b423a003149 SHA-1: 80d5d986123ed0ee6f67c5840f986aa1103abf69 SHA-256: 558d79cfe52dc6bfc0d9e7c8c5bebeebec5890c3876fb9806921598cb2350059
152 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, with one specifically identified as a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body appears to be malformed or encoded, but the presence of the malicious URL and the link farm heuristic suggest a phishing or redirection attempt to deliver a secondary payload.

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=%25D0%25BF%25D1%2580%25D0%25BE%25D1%2588%25D0%25B8%25D0%25B2%25D0%25BA%25D0%25B0+x+digital+tab+700
    • https://static.usrfiles.com/ugd/b8c837_86b8e7b476734cdd85e02ed1c7314eeb.pdf
    • https://static.usrfiles.com/ugd/b77b08_5ef934e12e71411f803f91ddf9a1f227.pdf
    • https://static.usrfiles.com/ugd/a2e20a_dd2a585919484f7881a594bab77a401e.pdf
    • https://cdn.shopify.com/s/files/1/0428/3518/1724/files/13226181179.pdf
    • https://cdn.shopify.com/s/files/1/0435/9513/7187/files/tunet.pdf
    • https://cdn.shopify.com/s/files/1/0429/6045/3785/files/docker_run_android_app.pdf
    • https://cdn.shopify.com/s/files/1/0433/7922/8833/files/opera_mini_8.pdf
    • https://cdn.shopify.com/s/files/1/0464/6735/0680/files/dirabixogosafimakamiros.pdf
    • https://static.usrfiles.com/ugd/f4de5e_d975fd14c6ad4da5b818135491ee3165.pdf
    • https://static.usrfiles.com/ugd/4bb894_1119b250fb7b4a22a41abe3fa13f24bf.pdf
    • https://static.usrfiles.com/ugd/b8c837_cfc2266b12354d6bb593e96dbaea740c.pdf
    • https://static.usrfiles.com/ugd/2f3ac6_5ca27e7046ee4f9689ef21d7e9dc87af.pdf
    • https://static.usrfiles.com/ugd/80c1db_c19cf269344348e481d1437c53157195.pdf
    • https://static.usrfiles.com/ugd/73f3b0_f92d73f805f840e4b10cdf0252ea39e2.pdf
    • https://static.usrfiles.com/ugd/ae15ca_b917546aeef447bc8908c644d96adc96.pdf
    • https://static.usrfiles.com/ugd/b8c837_d3b7170ea93f486198b35239bbecb89d.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_off000064a4.bin
836cb57dfbe64cf74812ffa219cab01959e554be982e01c3a14e14bc04563e09
pdf-font-stream PDF embedded font (sfnt) at offset 0x64A4 5920 bytes
font_01_sfnt_off00007800.bin
23426ccb26c6efee4a4b97e5d51c9e9e53dff8697c238656bfc5228e448b616c
pdf-font-stream PDF embedded font (sfnt) at offset 0x7800 16340 bytes