Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac850601a5b90ab1…

MALICIOUS

PDF

39.1 KB Created: 2020-08-03 17:24:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 22aeee7b9d9ec58341a5128ab9a9f7d8 SHA-1: 000fff7eb80caba63304fd15307efdb5cdb309f0 SHA-256: ac850601a5b90ab1e6de84f36dd5a7a1f361d821be738f06620e8e3d6c3d1745
154 Risk Score

Malware Insights

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

The PDF contains a heuristic firing for a malicious redirector link, which is a common technique for delivering malware or phishing pages. The document body, though heavily obfuscated, contains a URL that appears to be part of this redirection chain. The presence of numerous external links, many hosted on Shopify, suggests a link farm designed to improve SEO for malicious content. The ML classifier strongly indicates malicious intent.

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/pify?keyword=chemistry+formulas+pdf
    • http://files.colleengeorges.com/uploads/1/3/1/4/131406473/a921fe6ff3d39.pdf
    • http://files.thepoppyrocksball.co.uk/uploads/1/3/0/8/130813526/8555866.pdf
    • http://files.carlylbodnar.com/uploads/1/3/0/7/130775528/0d19677667d6211.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/86372263330.pdf
    • https://cdn.shopify.com/s/files/1/0436/7230/5817/files/loxewu.pdf
    • https://cdn.shopify.com/s/files/1/0431/7180/7381/files/dedejuku.pdf
    • https://cdn.shopify.com/s/files/1/0433/5471/8358/files/99699232047.pdf
    • https://cdn.shopify.com/s/files/1/0435/7187/1912/files/tudanurugevofemufibasik.pdf
    • https://cdn.shopify.com/s/files/1/0434/2897/0647/files/xokeso.pdf
    • https://cdn.shopify.com/s/files/1/0430/9526/1348/files/xusij.pdf
    • https://cdn.shopify.com/s/files/1/0434/0934/2621/files/54726347502.pdf
    • https://cdn.shopify.com/s/files/1/0450/4797/1990/files/ekms_1b.pdf
    • https://cdn.shopify.com/s/files/1/0433/4931/1646/files/74457912719.pdf
    • https://cdn.shopify.com/s/files/1/0437/3990/6197/files/loken_s_final_words_to_odyn.pdf
    • https://cdn.shopify.com/s/files/1/0437/3879/2085/files/21774422560.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_off00005be5.bin
9ef3c9f80ed23f90bcb56690ec822caebbdb026e4bae8ad1d6d5d0a26863ab32
pdf-font-stream PDF embedded font (sfnt) at offset 0x5BE5 5288 bytes
font_01_sfnt_off00006db7.bin
7178da9b66572e4be088f0eef14fe30c176d28bc3117db7232bfc7e8e3893348
pdf-font-stream PDF embedded font (sfnt) at offset 0x6DB7 9932 bytes