Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cc1682d087b4460…

MALICIOUS

PDF

48.5 KB Created: 2020-09-07 04:22:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2977c3c5aeb262488d8edf18a4d42b26 SHA-1: 98ea1d69499acb3acb9e7f9f5aa66bc00f2041d9 SHA-256: 9cc1682d087b44603a7af3ac87769461e31b7e13bcc7ecc52e3d65d1d0772d93
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a link disguised as interview questions, which redirects to a known malicious URL. The ML classifier strongly indicates maliciousness. The document body, though partially corrupted, contains the lure text and the malicious URL. The PDF also contains a link farm pointing to various PDF files, likely for SEO manipulation or to host further payloads.

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.link/wix?keyword=hospital+pharmacist+interview+questions+and+answers
    • https://static.usrfiles.com/ugd/135178_38b5fd08bb2b481fbe1c17af49f7887a.pdf
    • https://static.usrfiles.com/ugd/ef7b09_9e9a82e20b554180805f04a3c295b7d3.pdf
    • https://static.usrfiles.com/ugd/b8c837_643fd96829174a5bada6054e7027b46e.pdf
    • https://static.usrfiles.com/ugd/81d6a4_e48c8fbaf0364313850768599d70425c.pdf
    • https://cdn.shopify.com/s/files/1/0440/6276/9302/files/rusux.pdf
    • https://cdn.shopify.com/s/files/1/0433/5271/9515/files/tivuzixa.pdf
    • https://cdn.shopify.com/s/files/1/0432/5706/9721/files/felapaxazizawugumalexivud.pdf
    • https://static.usrfiles.com/ugd/68ec51_608996c74cbe4001a1c0830ff37b4e56.pdf
    • https://static.usrfiles.com/ugd/ca32a8_0fff55c1c3c14158a8b838ee6a5f18aa.pdf
    • https://static.usrfiles.com/ugd/b8c837_72352fd0c4b34e00962835f64b96ee3c.pdf
    • https://static.usrfiles.com/ugd/9cfd0a_b906a1c4083c4e83aa5f7da867bdfa0c.pdf
    • https://static.usrfiles.com/ugd/f0e51d_99694f7c8e614929a3b6ab181419b599.pdf
    • https://static.usrfiles.com/ugd/64e449_d91efb960b83499bbeed4eee13e1d4d8.pdf
    • https://static.usrfiles.com/ugd/4479ed_5f6298e7e6fd44aca53ad7c30921c974.pdf
    • https://static.usrfiles.com/ugd/72216b_ae2583369c3b4f8ab45b48fbbb67fab9.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_off00007f00.bin
f179c62e5bd7f977dacb93e744d5cff986bb52a06506942dd1d811612135d558
pdf-font-stream PDF embedded font (sfnt) at offset 0x7F00 5552 bytes
font_01_sfnt_off000091c2.bin
d2a4657669ae1e77a3f5414a1e779c92abe0bb59809b67965bb0f83b4e7e835c
pdf-font-stream PDF embedded font (sfnt) at offset 0x91C2 10428 bytes