Malicious PDF — malware analysis report

Static analysis result for SHA-256 315f335a0daf1f4e…

MALICIOUS

PDF

47.5 KB Created: 2020-08-30 16:01:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 38ce2f345349b3b1463a6e383aecc655 SHA-1: 1b1e76090a4b731942eacc5d069e3413d3ac4b40 SHA-256: 315f335a0daf1f4eb13e3d54f5bb849b7cf86d05e250c4ec0f1ceafb4c16e71b
152 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.com, which is disguised as an 'Aptis vocabulary test pdf'. The document also includes a large number of links to other PDFs, many hosted on shopify.com and static.usrfiles.com, suggesting a link farm or SEO poisoning tactic. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted, but the primary attack vector appears to be social engineering via a malicious link.

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=aptis+vocabulary+test+pdf
    • https://cdn.shopify.com/s/files/1/0435/0250/2048/files/genonitan.pdf
    • https://cdn.shopify.com/s/files/1/0430/8592/2466/files/72705837158.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/gekisemegudifusoledo.pdf
    • https://static.usrfiles.com/ugd/9904c2_187b19d606f3482997ab9de65d0703c8.pdf
    • https://static.usrfiles.com/ugd/d55797_aad83cb436ec4f9092405b899f2a7317.pdf
    • https://static.usrfiles.com/ugd/b8c837_e715faea046f4d9eb43389ae93912a61.pdf
    • https://static.usrfiles.com/ugd/5b9a87_904d93a17d93470da2059d53d5467246.pdf
    • https://static.usrfiles.com/ugd/01e791_12e25088d8c0418697515ed69c4463d4.pdf
    • https://static.usrfiles.com/ugd/57c819_965e9f690eb04e10ad7d2f65dbe8c6c0.pdf
    • https://static.usrfiles.com/ugd/6c98bc_c5b4e7a9387b45eb82add214435becfd.pdf
    • https://static.usrfiles.com/ugd/b8c837_2be2b8c580584df0ae00f4b5383ff0ce.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000062da.bin
f7356483ebc50f384f4d05165a5b0b23facdbb381107f9873f7b8480ea88d88f
pdf-font-stream PDF embedded font (sfnt) at offset 0x62DA 5440 bytes
font_01_sfnt_off00007568.bin
05ca70582e2ba7eaf92a66b98c2003c92012dd229c751f94f37d224081252a07
pdf-font-stream PDF embedded font (sfnt) at offset 0x7568 11496 bytes
font_02_sfnt_off00009bd4.bin
531e37f64a2e7dc3bfb257675d9e6c644c7b1597f33ba9a969cd005a7ed65660
pdf-font-stream PDF embedded font (sfnt) at offset 0x9BD4 16312 bytes