Malicious PDF — malware analysis report

Static analysis result for SHA-256 830fbfe3efb08822…

MALICIOUS

PDF

41.4 KB Created: 2020-08-11 23:14:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6bd0bb67125500b6ad1311b8e9210616 SHA-1: 33dcf05f4165271f34dee3c6bb0271510fe19e8b SHA-256: 830fbfe3efb08822a91069a276bab12641c11f3437583aa63d0b7f7af75796c5
154 Risk Score

Malware Insights

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

The PDF contains a link farm of numerous external PDF files, with one link pointing to a known malicious redirector. This suggests a tactic to distribute malicious content or phishing pages. The ML classifier also strongly indicated maliciousness.

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/wb?keyword=ejusdem%20generis%20rule%20pdf
    • http://files.stevemager.com/uploads/1/3/0/9/130969402/1406598.pdf
    • http://dujit.1corinthiens15.com/uploads/1/3/1/8/131856380/nobabosevo-dutitolalerek-gopesowam-wovusamewuf.pdf
    • http://files.junyeo.com/uploads/1/3/1/3/131380627/tukelijupoperelek.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/8449/6550/files/dizugufusufowabavavesuxar.pdf
    • https://cdn.shopify.com/s/files/1/0429/7441/2949/files/97625471818.pdf
    • https://cdn.shopify.com/s/files/1/0429/2778/4103/files/70475832722.pdf
    • https://cdn.shopify.com/s/files/1/0433/8191/5809/files/bluedio_t2_user_manual.pdf
    • https://cdn.shopify.com/s/files/1/0432/0601/7186/files/advanced_engineering_mathematics_5th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0440/1568/1701/files/81774021997.pdf
    • https://cdn.shopify.com/s/files/1/0431/1102/2756/files/12941508837.pdf
    • https://cdn.shopify.com/s/files/1/0434/5665/9621/files/balancing_chemical_reactions_worksheet.pdf
    • https://cdn.shopify.com/s/files/1/0431/3900/6632/files/advanced_mathematics_an_incremental_development_solutions_manual_free.pdf
    • https://cdn.shopify.com/s/files/1/0430/6498/3703/files/kosejuxirozo.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000630b.bin
14aee8a3dbea80a5f9e05b1dfe9ae78d30a2f39bc659453a99671e1c3d71ee64
pdf-font-stream PDF embedded font (sfnt) at offset 0x630B 5184 bytes
font_01_sfnt_off0000749c.bin
d12144c5375f5299a95987ea49402901399e07416db594193909995adeaf9a46
pdf-font-stream PDF embedded font (sfnt) at offset 0x749C 10648 bytes