Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecfe16e8c9f0f886…

MALICIOUS

PDF

44.1 KB Created: 2020-08-01 02:14:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1f68589b8a55fb5b9c311faec01c991a SHA-1: 2e66c7b0286f930e5410aeeaf5a5937994202c26 SHA-256: ecfe16e8c9f0f88688728d161a67e3dc86579e8d80ee241d3352713a82820f94
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a mass of external links, including one pointing to a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though malformed, contains a URL that is also present in the heuristics, suggesting a lure to a malicious site. The presence of numerous PDF links, many hosted on Shopify, indicates a link farm designed to distribute malicious 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.ru/pify?keyword=binary+tree+copy+constructor
    • http://files.swiftekconsulting.com/uploads/1/3/1/8/131856398/807cc94e.pdf
    • http://files.dough-factory.com/uploads/1/3/1/4/131455621/lolexituzofo.pdf
    • http://files.cornflowerglass.com/uploads/1/3/2/7/132740253/supelaligarug.pdf
    • http://files.artistreecavaliers.com/uploads/1/3/0/9/130969489/lakawewe.pdf
    • https://cdn.shopify.com/s/files/1/0432/9812/8036/files/52527030488.pdf
    • https://cdn.shopify.com/s/files/1/0429/2031/2991/files/gutiwadawixozipafupixug.pdf
    • https://cdn.shopify.com/s/files/1/0438/4253/5574/files/82586665670.pdf
    • https://cdn.shopify.com/s/files/1/0427/6980/9564/files/38278105010.pdf
    • https://cdn.shopify.com/s/files/1/0433/3459/8809/files/83361349596.pdf
    • https://cdn.shopify.com/s/files/1/0429/8617/6675/files/polawizobilexagujigitajo.pdf
    • https://cdn.shopify.com/s/files/1/0435/6803/8049/files/balujemalunejixevafebu.pdf
    • https://cdn.shopify.com/s/files/1/0429/8201/5129/files/18030476968.pdf
    • https://cdn.shopify.com/s/files/1/0431/2743/9526/files/2602043369.pdf
    • https://cdn.shopify.com/s/files/1/0428/5143/4659/files/10445320627.pdf
    • https://cdn.shopify.com/s/files/1/0432/7024/2460/files/relax.pdf
    • https://cdn.shopify.com/s/files/1/0427/7937/7830/files/33592063099.pdf
    • https://cdn.shopify.com/s/files/1/0433/5537/3720/files/83798720967.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_off0000659b.bin
172db95b8a7e87e971d79c7764e851ccd381057270f489defa161c50150b12c6
pdf-font-stream PDF embedded font (sfnt) at offset 0x659B 5048 bytes
font_01_sfnt_off000076de.bin
ea26dde46252a9d7dd14431209117ec55c8bf41e284b770136787419fcc7ec97
pdf-font-stream PDF embedded font (sfnt) at offset 0x76DE 14096 bytes