Malicious PDF — malware analysis report

Static analysis result for SHA-256 91b8c54fa013930d…

MALICIOUS

PDF

38.4 KB Created: 2020-07-24 18:42:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 28a7fd9e0507485696d0e187fe7862d9 SHA-1: af10819ca43e9345f1608d88d1e519ac4cf6ebdc SHA-256: 91b8c54fa013930d8fb7ac861ca76a82396128c19c67d684f6ec9741e469217e
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains a mass external link farm, with a primary link pointing to a known malicious redirector. The document body, though heavily obfuscated, suggests a lure related to an 'internet speed metre apk'. The presence of numerous PDF links, many hosted on Shopify, indicates an attempt to distribute malicious content or phish users. The ML classifier strongly flagged this PDF as malicious.

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.com/pify?keyword=internet+speed+metre++apk
    • http://files.piemontereview.com/uploads/1/3/1/1/131164067/japin-mikolopor-joxifizaleli.pdf
    • http://files.calicocreekfeedandpets.com/uploads/1/3/0/7/130738765/304241.pdf
    • http://files.carlinvillefire.com/uploads/1/3/1/3/131397964/777321.pdf
    • http://files.learningtobuyahome.com/uploads/1/3/1/3/131384145/5941752.pdf
    • http://files.skunkscuttinghorses.com/uploads/1/3/0/7/130740262/aa5c1868.pdf
    • http://files.calicocreekfeedandpets.com/uploads/1/3/0/7/1307
    • https://cdn.shopify.com/s/files/1/0428/7073/5014/files/58499222529.pdf
    • https://cdn.shopify.com/s/files/1/0433/7342/8888/files/jezibixubevi.pdf
    • https://cdn.shopify.com/s/files/1/0428/3216/7068/files/kekinuma.pdf
    • https://cdn.shopify.com/s/files/1/0429/6101/0842/files/90631500225.pdf
    • https://cdn.shopify.com/s/files/1/0427/9658/1020/files/81988296546.pdf
    • https://cdn.shopify.com/s/files/1/0428/2381/1239/files/volexovumonu.pdf
    • https://cdn.shopify.com/s/files/1/0431/7328/1948/files/65748290730.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/gekisemegudifusoledo.pdf
    • https://cdn.shopify.com/s/files/1/0436/1856/6306/files/86491615999.pdf
    • https://cdn.shopify.com/s/files/1/0434/7294/5312/files/nabofavutisivesesibefakot.pdf
    • https://cdn.shopify.com/s/files/1/0429/3849/9235/files/raputefigobagaz.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_off00005d34.bin
10e4d3e62466a9f9f0e89f36c3f469373633c8435c98a810090d8a09764b582d
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D34 4704 bytes
font_01_sfnt_off00006cfc.bin
658c141c7737412cac4de30d1120db891fc7caec3e2a0132342449c2af6d9db9
pdf-font-stream PDF embedded font (sfnt) at offset 0x6CFC 9284 bytes