Malicious PDF — malware analysis report

Static analysis result for SHA-256 c0dff0f01fb14ad3…

MALICIOUS

PDF

46.4 KB Created: 2020-08-31 06:11:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c99829bd57149fa4a724ff9a3f27b188 SHA-1: ece3c52f683bd21848713d9bd703b2031906bb32 SHA-256: c0dff0f01fb14ad30ca49a270c3a53c3a6257da4d528a98dbc7983cdb27b2cd0
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.001 Malicious Link

The PDF contains a link to a known malicious redirector infrastructure, identified by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The ML classifier also strongly flagged this PDF as malicious. The embedded URL points to a page designed to lure users with 'grade 2 reading comprehension' content, which then redirects to a malicious site.

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=grade+2+reading+comprehension
    • https://static.usrfiles.com/ugd/b8c837_7eb12e43ac1a4dfba1729cfb09986dba.pdf
    • https://static.usrfiles.com/ugd/f515ca_4412d9caf81b4e73b6ac3263205db1d1.pdf
    • https://static.usrfiles.com/ugd/b8c837_972a347c37134841bd889e0d19d56688.pdf
    • https://static.usrfiles.com/ugd/c7ef1a_6603ef0782ca425abe5af0ab0030a0bb.pdf
    • https://static.usrfiles.com/ugd/3aee12_8cfbaa69963e4a1a846db5de98efe34c.pdf
    • https://static.usrfiles.com/ugd/7198c1_11a8dcb8d2da4ca4b1d6f6adafd668be.pdf
    • https://static.usrfiles.com/ugd/c8a981_6c36ffd6bae94c7aba1dfa7cf286841c.pdf
    • https://static.usrfiles.com/ugd/b8c837_d76afc95570843bbb83e292015836584.pdf
    • https://cdn.shopify.com/s/files/1/0461/6129/7560/files/spot_the_difference_printable_black.pdf
    • https://cdn.shopify.com/s/files/1/0430/6403/3429/files/xikofumuve.pdf
    • https://cdn.shopify.com/s/files/1/0437/0399/2485/files/bixovekimogofijowakor.pdf
    • https://cdn.shopify.com/s/files/1/0437/6595/6759/files/sejarah_belanda_masuk_ke_indonesia.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/
    • https://static.usrfiles.com/ugd/b8c837_7eb12e43ac1a4dfb

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007746.bin
701603a2ef46619541645aa664faf7ccdc6b90b64e14317b7a4894bf15a5be9b
pdf-font-stream PDF embedded font (sfnt) at offset 0x7746 5620 bytes
font_01_sfnt_off00008a3d.bin
1f258f59a0d5f19546095ebf7c15b93af5f08381dbcee90701b99865e70c7e9b
pdf-font-stream PDF embedded font (sfnt) at offset 0x8A3D 10036 bytes