Malicious PDF — malware analysis report

Static analysis result for SHA-256 26b81ff4044c367a…

MALICIOUS

PDF

35.6 KB Created: 2020-08-08 23:55:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dbce812d966c97638c1551793774cf26 SHA-1: f3a9ae5e7be70780aba57f98f0b1dfbd83dd9e07 SHA-256: 26b81ff4044c367a01edafcddd9d5c1487ba3055ef3e2af759bffcc6ef6b2b58
154 Risk Score

Malware Insights

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

The PDF file contains a critical heuristic firing indicating a malicious redirector link. The document body, though heavily obfuscated, contains the URL 'https://ttraff.com/pify?keyword=bobrick+grab+bars+pdf', which is also listed as a malicious redirector. The presence of numerous links to Shopify-hosted PDFs suggests a link farm or SEO poisoning technique to disguise malicious intent. The ML classifier also 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/pify?keyword=bobrick+grab+bars+pdf
    • http://files.ymcalift.com/uploads/1/3/0/7/130740193/8f07a4b24.pdf
    • http://jafoja.fantasticalfaces.com/uploads/1/3/1/8/131856543/6552886.pdf
    • http://files.jewelrybytraditions.com/uploads/1/3/1/6/131607712/nuredixotudej.pdf
    • http://files.pattibounds.com/uploads/1/3/1/4/131453684/begidosut-xukobopajini.pdf
    • https://cdn.shopify.com/s/files/1/0433/6618/7176/files/giant_egg_classic_wow.pdf
    • https://cdn.shopify.com/s/files/1/0431/7744/3483/files/muwefumabatid.pdf
    • https://cdn.shopify.com/s/files/1/0435/5633/9871/files/4534375854.pdf
    • https://cdn.shopify.com/s/files/1/0431/7921/2960/files/delete_commits_github.pdf
    • https://cdn.shopify.com/s/files/1/0439/2806/0059/files/zabatoxurovomadibog.pdf
    • https://cdn.shopify.com/s/files/1/0432/4674/7803/files/nibinilawinulizuju.pdf
    • https://cdn.shopify.com/s/files/1/0434/0488/6166/files/84724752611.pdf
    • https://cdn.shopify.com/s/files/1/0436/1460/1378/files/kabeniso.pdf
    • https://cdn.shopify.com/s/files/1/0449/5550/0712/files/dan_abnett_pariah.pdf
    • https://cdn.shopify.com/s/files/1/0433/1700/2405/files/puribibifidofipaso.pdf
    • https://cdn.shopify.com/s/files/1/0436/4845/0718/files/fikopupejup.pdf
    • https://cdn.shopify.com/s/files/1/0427/7387/2807/files/52740229003.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_off00004c09.bin
db21d292da34ddb4b49eddde8cb1eef4f96d42724512a46f8230b79a378446e6
pdf-font-stream PDF embedded font (sfnt) at offset 0x4C09 5544 bytes
font_01_sfnt_off00005ef6.bin
a393fbb928dbf8546e0b4c0effe13c947fd8beb7eada2f76432ae58f42b22976
pdf-font-stream PDF embedded font (sfnt) at offset 0x5EF6 10212 bytes