Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c8a93b5d85b35f4…

MALICIOUS

PDF

134.5 KB Created: 2020-08-31 11:24:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8d8bd94bdb34289d0c56be1524e39816 SHA-1: e613889af56804e9d6a6296fc7c77c9b0a54fe22 SHA-256: 0c8a93b5d85b35f4b578c182552e8b430e9e56c8075d78ce13e124d924d11087
154 Risk Score

Malware Insights

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

The PDF contains embedded links that redirect to a malicious domain, identified by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though heavily obfuscated, contains text suggesting it is a car maintenance log, likely a lure. The ML classifier also strongly indicated maliciousness. The primary IOC is the malicious redirector URL.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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.me/wix?keyword=carnet+d%2527+entretien+citroen+berlingo
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://cdn.shopify.com/s/files/1/0428/6640/9639/files/71844655442.pdf
    • https://cdn.shopify.com/s/files/1/0431/2170/5124/files/pusokuxusazojejafewak.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/19085525902.pdf
    • https://cdn.shopify.com/s/files/1/0430/4565/0586/files/calculus_a_complete_course_download.pdf
    • https://cdn.shopify.com/s/files/1/0433/8722/4214/files/patabuvomalosufujera.pdf
    • https://cdn.shopify.com/s/files/1/0430/0118/4417/files/newizasa.pdf
    • https://cdn.shopify.com/s/files/1/0436/9960/1558/files/drivers_guide_alberta_practice_test.pdf
    • https://static.usrfiles.com/ugd/b8c837_4db56a3895fa4965a81bf66695c320eb.pdf
    • https://static.usrfiles.com/ugd/e5a943_9f9ff9255a8b4b8ab64fcd885405b7f4.pdf
    • https://static.usrfiles.com/ugd/2c608b_6759869f07ac41f78e5b16826fade8fb.pdf
    • https://static.usrfiles.com/ugd/d7ba0f_764ef0f615fc41e88ec4764a1af15e7b.pdf
    • https://static.usrfiles.com/ugd/b8c837_45aaa70368c748eabbcd910d550aa9b3.pdf
    • https://static.usrfiles.com/ugd/b8c837_c970f4ca78c74065a324323e999182f0.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_off0001b774.bin
0ca1a810c36f418dd2ad74686904324a7a9a3f2d65318760b797aab2d14750e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B774 4916 bytes
font_01_sfnt_off0001c835.bin
6b527c155c144afddd77acc1871d4f426422a1d7a02efe33d73dfa8cbeae07b8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1C835 17940 bytes
font_02_sfnt_off0001fc7e.bin
0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333
pdf-font-stream PDF embedded font (sfnt) at offset 0x1FC7E 4324 bytes