Malicious PDF — malware analysis report

Static analysis result for SHA-256 88421cc8ffe7827e…

MALICIOUS

PDF

51.8 KB Created: 2020-08-20 02:38:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d741156cb3a4b9bbcf155aab1fb4e749 SHA-1: ed54751e8b0aec34261736b6bc4105c27eb18299 SHA-256: 88421cc8ffe7827e6ddc3bffd19c1d63238610ead5601266ac26204c1c026292
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a heuristic firing for a malicious redirector link, pointing to 'https://ttraff.cc/pify?keyword=burrows+wheeler+transform+decode'. Additionally, it exhibits characteristics of a PDF link farm, with numerous embedded URLs, many of which are benign but serve to obscure the malicious intent. The ML classifier strongly indicates maliciousness. No scripts were extracted, but the embedded URL is the primary indicator of malicious activity.

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.cc/pify?keyword=burrows+wheeler+transform+decode
    • http://files.aera100.net/uploads/1/3/0/7/130740097/37431e65.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://cdn.shopify.com/s/files/1/0432/3010/1668/files/zemebige.pdf
    • https://cdn.shopify.com/s/files/1/0431/0879/4530/files/tuzetexaxisafokak.pdf
    • https://cdn.shopify.com/s/files/1/0431/1410/2951/files/58050032928.pdf
    • https://cdn.shopify.com/s/files/1/0427/7937/7830/files/81765288301.pdf
    • https://cdn.shopify.com/s/files/1/0435/2750/4032/files/wosonepidabavifo.pdf
    • https://cdn.shopify.com/s/files/1/0438/4302/7106/files/appraisal_theory.pdf
    • https://cdn.shopify.com/s/files/1/0428/1312/8867/files/lazunixelokudapirapapat.pdf
    • https://cdn.shopify.com/s/files/1/0430/9201/7305/files/49125713379.pdf
    • https://cdn.shopify.com/s/files/1/0432/7990/9030/files/88611290516.pdf
    • https://cdn.shopify.com/s/files/1/0428/5507/1900/files/fenapin.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007ecf.bin
353f607bf2d090f63b5828ee95574721d71333f4cbce7f8a5695a8a51a63b77d
pdf-font-stream PDF embedded font (sfnt) at offset 0x7ECF 5236 bytes
font_01_sfnt_off00009087.bin
4241ea85b440c870fe395759cbbe61726169906ac79cde7bb3020fbe9dc7e469
pdf-font-stream PDF embedded font (sfnt) at offset 0x9087 10736 bytes
font_02_sfnt_off0000b460.bin
05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176
pdf-font-stream PDF embedded font (sfnt) at offset 0xB460 4324 bytes