Malicious PDF — malware analysis report

Static analysis result for SHA-256 8559fbda38a8efcd…

MALICIOUS

PDF

42.5 KB Created: 2020-08-31 21:20:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 192fab46b49992b2440aa2c435867a73 SHA-1: 4da42c5cb25470c72d9a7d5a247db343892e7301 SHA-256: 8559fbda38a8efcd1b80f32e0ae7145778b19ca6b3dd41f3ee87559a5b26aed8
152 Risk Score

Malware Insights

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

The PDF contains multiple embedded links, with one specifically pointing to a known malicious redirector infrastructure (ttraff.com). The document body, though heavily obfuscated, contains text related to 'medical certificate format for college admission pdf', suggesting a lure. The presence of numerous external PDF links, many hosted on Shopify, indicates a link farm strategy, likely to obscure the malicious redirector. The ML classifier strongly flagged this PDF as malicious.

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=medical+certificate+format+for+college+admission+pdf
    • https://cdn.shopify.com/s/files/1/0438/1586/2434/files/hypixel_pe_ip.pdf
    • https://cdn.shopify.com/s/files/1/0430/1769/9477/files/rewebemekinanureti.pdf
    • https://cdn.shopify.com/s/files/1/0430/7399/4905/files/20824854939.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/bokowolexom.pdf
    • https://static.usrfiles.com/ugd/1849a1_0a43f38097d8475ea8b330d4f1b08fb8.pdf
    • https://static.usrfiles.com/ugd/04e6f9_e0a6110e07944ee882bbe5f4a7c3f863.pdf
    • https://static.usrfiles.com/ugd/930050_ccf3fab763544ddeafb12c1740f51457.pdf
    • https://static.usrfiles.com/ugd/b8c837_df685358f3244444b989f5a7620b5a96.pdf
    • https://static.usrfiles.com/ugd/2b25b5_9f0688198acc48a38e3f2784b6f11453.pdf
    • https://static.usrfiles.com/ugd/eb5a6a_9198ce021cee43789918aee420ca4e5d.pdf
    • https://static.usrfiles.com/ugd/bb13a2_9be8e04f118d49b3a3a9b180e90be2cc.pdf
    • https://static.usrfiles.com/ugd/83d902_4bd3147e328a4c3ca71830e0db0ef615.pdf
    • https://static.usrfiles.com/ugd/b8c837_7bc36a9f5104486ca7fc52d0f3f10884.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_off00006677.bin
125dffb296cdc1a30aa7b615d668880af89cdc297c79c153875582e164d2b058
pdf-font-stream PDF embedded font (sfnt) at offset 0x6677 5480 bytes
font_01_sfnt_off00007911.bin
131479faefeb96fc8c20f142ecdb90b41769787f7c04fbc35ed48a806bb60aeb
pdf-font-stream PDF embedded font (sfnt) at offset 0x7911 10368 bytes