Malicious PDF — malware analysis report

Static analysis result for SHA-256 6cb71b50cb610be9…

MALICIOUS

PDF

51.6 KB Created: 2020-08-12 04:26:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9d9b18f955890b1b3548fac9cc518675 SHA-1: ecccc7902bc3c0d9660211c7a8dd1e2f420e13da SHA-256: 6cb71b50cb610be9878124afd2c2375f03723040c5d99aeebeaeaf14ad0f86d4
154 Risk Score

Malware Insights

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

The PDF contains numerous links, including one identified as a malicious redirector, disguised as a document download. The ML classifier strongly indicates maliciousness, and the presence of many external PDF links suggests a link farm or SEO poisoning attempt. The primary malicious IOC is the redirector URL, which likely leads to further stages of infection.

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=mechanical+drawing+standards+manual+pdf
    • http://files.brightsidesolutions.com/uploads/1/3/0/7/130775017/medoputiziloj-bader.pdf
    • http://files.bridgeportrodandgunny.com/uploads/1/3/0/8/130874204/46ddfa10321e6b.pdf
    • http://xukasa.tmi-photo.com/uploads/1/3/0/8/130814328/9445281.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/4190/7110/files/motegixenosovukaralapa.pdf
    • https://cdn.shopify.com/s/files/1/0438/6209/8085/files/zefilufumoses.pdf
    • https://cdn.shopify.com/s/files/1/0434/8765/8141/files/nostradamus_almanac_pdf.pdf
    • https://cdn.shopify.com/s/files/1/0434/0151/1064/files/mumiped.pdf
    • https://cdn.shopify.com/s/files/1/0432/7990/9028/files/88370835106.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/mevadijuxirefasu.pdf
    • https://cdn.shopify.com/s/files/1/0430/2936/4889/files/topamuj.pdf
    • https://cdn.shopify.com/s/files/1/0432/9776/7592/files/noxavuzasinekaduj.pdf
    • https://cdn.shopify.com/s/files/1/0434/6894/7616/files/wodot.pdf
    • https://cdn.shopify.com/s/files/1/0435/5493/0839/files/jarakoremud.pdf
    • https://cdn.shopify.com/s/files/1/0431/2875/0234/files/is_cs._money_legit.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_off00007ab6.bin
4b5aadfc7702beeb1de5dfcd45c9e8fa63c88b5d9bea9460a91c2c3b294dc04b
pdf-font-stream PDF embedded font (sfnt) at offset 0x7AB6 5668 bytes
font_01_sfnt_off00008de3.bin
3717daacf2ab03cf4dfb530f38ab377506b645069092bda7141008ee7a03f98f
pdf-font-stream PDF embedded font (sfnt) at offset 0x8DE3 16124 bytes