Malicious PDF — malware analysis report

Static analysis result for SHA-256 8941a5a3eb8c7085…

MALICIOUS

PDF

43.4 KB Created: 2020-08-30 22:19:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: db5a1016bcdffc9555f98e86372c83de SHA-1: a938194d49eadc887494ecb148829f17bdf47e33 SHA-256: 8941a5a3eb8c7085f50d2df7716ca9768621f1c7f95fd1f261e6f191cb41bdd7
152 Risk Score

Malware Insights

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

The PDF file contains a link that redirects to a malicious URL, disguised with a keyword suggesting a useful template. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK confirms the malicious nature of the redirector. The PDF also contains a large number of external links, many hosted on Shopify, likely part of a link farm to improve SEO for malicious content. No scripts were extracted, but the primary attack vector appears to be social engineering via a malicious link.

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=excel+checkbook+template
    • https://cdn.shopify.com/s/files/1/0433/6808/7711/files/71963417814.pdf
    • https://cdn.shopify.com/s/files/1/0430/3139/6503/files/bisewenag.pdf
    • https://cdn.shopify.com/s/files/1/0434/7245/3797/files/zejozotasodap.pdf
    • https://cdn.shopify.com/s/files/1/0430/6403/3429/files/dozimunulazobelosig.pdf
    • https://cdn.shopify.com/s/files/1/0463/2536/6945/files/thyroid_disease_in_pregnancy_guideline.pdf
    • https://cdn.shopify.com/s/files/1/0431/1928/0288/files/62738414179.pdf
    • https://cdn.shopify.com/s/files/1/0434/3942/3655/files/19820618698.pdf
    • https://cdn.shopify.com/s/files/1/0434/6281/9990/files/naming_alkenes_examples.pdf
    • https://cdn.shopify.com/s/files/1/0437/3161/5909/files/afcat_sample_papers_free.pdf
    • https://cdn.shopify.com/s/files/1/0440/8298/7173/files/puweturop.pdf
    • https://static.usrfiles.com/ugd/912de2_732547d1d27d489d9efcb12fb12e8535.pdf
    • https://static.usrfiles.com/ugd/36f25b_297905fcef0c444395dd3a80304ef7d4.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_off000063c6.bin
bff010857897069f9ce388124d202c82fcbb200ae5b936a2fd8a6fd4e465d64f
pdf-font-stream PDF embedded font (sfnt) at offset 0x63C6 5128 bytes
font_01_sfnt_off00007513.bin
ce9eec49524d0e1506c1704ca2cac9cb4816ed422df345c400a8b7078a0df909
pdf-font-stream PDF embedded font (sfnt) at offset 0x7513 14148 bytes