Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cd963079f046611…

MALICIOUS

PDF

35.9 KB Created: 2020-08-24 09:18:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 184ecfb84895f9e69fd54e3810eaa2a1 SHA-1: 887f2483a54a16d1e626e20e565991aab883a89d SHA-256: 9cd963079f0466111c79ea5e8f3d50d3a9cb8f08b1d7feee5b8802f242407009
152 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by an ML classifier and contains a critical heuristic indicating it links to known malicious redirector infrastructure. The document body itself is heavily obfuscated but contains numerous embedded URLs, many pointing to external PDFs hosted on various domains. This suggests a tactic to manipulate search engine results or to lure users into clicking potentially harmful links.

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=statistical+learning+theory+vapnik+pdf
    • http://files.sboaschoolmdu.org/uploads/1/3/1/4/131408371/87f75.pdf
    • http://files.unitedkingdomvintage.com/uploads/1/3/0/7/130740517/kegizojikobiti.pdf
    • http://files.buyalphabetphotos.com/uploads/1/3/1/3/131379117/zidovoxa.pdf
    • http://files.arthitparade.net/uploads/1/3/0/7/130776103/wafasapivabadone.pdf
    • http://derelo.illuminated-engraving.com/uploads/1/3/1/8/131857334/borunilafinojek_komewazigu.pdf
    • https://cdn.shopify.com/s/files/1/0432/4347/1008/files/aristotle_nicomachean_ethics_book_7.pdf
    • https://cdn.shopify.com/s/files/1/0434/6196/8025/files/pipodubedizowowirunadoxe.pdf
    • https://cdn.shopify.com/s/files/1/0431/6558/1468/files/mesilonofaguziru.pdf
    • https://cdn.shopify.com/s/files/1/0437/9528/4130/files/64105594260.pdf
    • https://cdn.shopify.com/s/files/1/0431/6492/6111/files/laviwilulofezuledigipe.pdf
    • https://cdn.shopify.com/s/files/1/0430/7963/1012/files/tuvetivinegum.pdf
    • https://cdn.shopify.com/s/files/1/0434/5351/3893/files/fiwapexixefo.pdf
    • https://cdn.shopify.com/s/files/1/0429/7100/5082/files/agkistrodon_bilineatus.pdf
    • https://cdn.shopify.com/s/files/1/0448/1833/3858/files/tepivilodozifeja.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_off00004ecc.bin
81970ac0fe4c5d442c3f8c0f075dc0e18724aacb6d675f40d5dae3e90e634c39
pdf-font-stream PDF embedded font (sfnt) at offset 0x4ECC 5744 bytes
font_01_sfnt_off0000624c.bin
665d6edc3f9b135d84cc8e61f217896b2ae6d4a8459f2cb21bb0a1e36589611a
pdf-font-stream PDF embedded font (sfnt) at offset 0x624C 9464 bytes