Malicious PDF — malware analysis report

Static analysis result for SHA-256 22c5420f02063bf8…

MALICIOUS

PDF

37.9 KB Created: 2020-08-02 21:25:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 285ef64547cbdc8e3c86d516d2bfe740 SHA-1: c6d0a77dc53aa530ec446123e333054e5fb07530 SHA-256: 22c5420f02063bf89a866c7eafd6c7f5b67d03f0349ed1a01f009b7f40a9c39f
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with one pointing to a known malicious redirector. The ML classifier strongly indicated maliciousness. The document body itself is heavily obfuscated and contains numerous URLs, many of which are hosted on Shopify and appear to be part of a link farm. The primary attack pattern observed is the use of a link farm to potentially distribute malicious content or manipulate search engine results.

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.ru/pify?keyword=oorel17cci+cloudapp+net
    • http://files.bibicafebakery.com/uploads/1/3/1/6/131636692/4396253.pdf
    • http://files.jrhewson.com/uploads/1/3/1/3/131379696/ganuveledesese-likutubezowi-xenowavukisad-vixexazek.pdf
    • http://files.understandingfantasybaseball.com/uploads/1/3/0/7/130775448/227ae79f2b.pdf
    • https://cdn.shopify.com/s/files/1/0434/9345/8070/files/gupokibuwosesaseweju.pdf
    • https://cdn.shopify.com/s/files/1/0430/8277/6725/files/87767914627.pdf
    • https://cdn.shopify.com/s/files/1/0430/7098/0247/files/2440530060.pdf
    • https://cdn.shopify.com/s/files/1/0432/3259/2040/files/perowowatebid.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/646255477.pdf
    • https://cdn.shopify.com/s/files/1/0430/0426/4601/files/funowanajexunu.pdf
    • https://cdn.shopify.com/s/files/1/0427/9923/5228/files/89700233470.pdf
    • https://cdn.shopify.com/s/files/1/0434/5082/6905/files/irc_college_books.pdf
    • https://cdn.shopify.com/s/files/1/0430/9018/2304/files/xisemuwo.pdf
    • https://cdn.shopify.com/s/files/1/0428/1086/7871/files/wibasaletoxemajizedu.pdf
    • https://cdn.shopify.com/s/files/1/0429/5612/8412/files/35715046068.pdf
    • https://cdn.shopify.com/s/files/1/0430/5797/1362/files/osrs_archery_guide.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_off000052f1.bin
c927e76cf301d180f5cb70c6aa715b863f274a44693b386a1badea015a168f76
pdf-font-stream PDF embedded font (sfnt) at offset 0x52F1 5048 bytes
font_01_sfnt_off00006434.bin
f0db999319fc7343dbe20b21c0a1947f50d05157658bcc01d28c47236dc51d63
pdf-font-stream PDF embedded font (sfnt) at offset 0x6434 10912 bytes