Malicious PDF — malware analysis report

Static analysis result for SHA-256 4de50e1f81ddaa41…

MALICIOUS

PDF

44.0 KB Created: 2020-08-30 23:29:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 375a419cd5b3724d3ff51b2a28b1ee4d SHA-1: 835c91ceb32aee9ebd7ac232f15aaefa41e74e63 SHA-256: 4de50e1f81ddaa41d6b5d1731f0ebca66efa96903dd185086909e44e4a78f9c5
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to numerous PDFs hosted on Shopify, with one of the initial links leading to a known malicious redirector. The ML classifier strongly flagged this PDF as malicious. The document body, though heavily obfuscated, contains the malicious URL and references to other PDF files, suggesting a lure to external content.

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/wix?keyword=manualidades+faciles+con+papel
    • https://cdn.shopify.com/s/files/1/0431/8288/2980/files/foxubupobonasuri.pdf
    • https://cdn.shopify.com/s/files/1/0433/5396/4702/files/golden_spoon_nutritional.pdf
    • https://cdn.shopify.com/s/files/1/0435/4480/5525/files/68155455253.pdf
    • https://cdn.shopify.com/s/files/1/0427/6905/5911/files/nuralefofa.pdf
    • https://cdn.shopify.com/s/files/1/0430/0872/1045/files/xarega.pdf
    • https://cdn.shopify.com/s/files/1/0431/6377/9240/files/movobomewulakuk.pdf
    • https://cdn.shopify.com/s/files/1/0448/1577/7954/files/autosar_compendium_part_1.pdf
    • https://cdn.shopify.com/s/files/1/0430/8385/8080/files/zigepunopi.pdf
    • https://static.usrfiles.com/ugd/b8c837_4d839e889e1743e389a3da0ab895b5a3.pdf
    • https://static.usrfiles.com/ugd/b8c837_8fb304e076964a2db177e8e091212e4c.pdf
    • https://static.usrfiles.com/ugd/b8c837_c0adad6502bf40ae8d924276af56824c.pdf
    • https://cdn.shopify.com/s/files/1/0428/8220/3811/files/mamesobifikute.pdf
    • https://cdn.shopify.com/s/files/1/0431/4074/3329/files/44616768071.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/kufanagapaxo.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_off00006eb9.bin
8c6830ba1c2bff9797a44a2922c1ca8db8933e72a153534b7a9f75649df5aedb
pdf-font-stream PDF embedded font (sfnt) at offset 0x6EB9 5056 bytes
font_01_sfnt_off00008004.bin
44387a7c1f89a1cbed0b122830d8b400e7439fe173ff7e80911cde09b06f88ac
pdf-font-stream PDF embedded font (sfnt) at offset 0x8004 10392 bytes