Malicious PDF — malware analysis report

Static analysis result for SHA-256 287ad0774cbbfdde…

MALICIOUS

PDF

45.0 KB Created: 2020-07-30 23:52:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f9f8d71d2034707a0437a6c2c0a8158b SHA-1: aa90018eb4d81c8b5c5490b79ff84bc0eb5095ae SHA-256: 287ad0774cbbfdde4d62f492e535b385043b75120e2f1911fb13a89df435f831
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic firing indicating it links to known malicious redirector infrastructure. The document body, though heavily obfuscated, suggests a lure related to a 'Couchbase tutorial for beginners pdf'. The primary malicious IOC is the redirector URL, which is likely used to funnel victims to further malicious content. The ML classifier strongly supports the malicious nature of this PDF.

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=couchbase+tutorial+for+beginners+pdf
    • http://files.genehamiltonartist.com/uploads/1/3/1/8/131871704/7686114.pdf
    • http://files.strozzimeowvellous.com/uploads/1/3/1/3/131398140/9294474.pdf
    • http://files.noarderljocht.com/uploads/1/3/1/4/131437984/reluwidiwarom.pdf
    • http://files.nikkosbread.com/uploads/1/3/0/7/130775649/magatuj_ribuwuvojiwim.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/wopesutokuvikoku.pdf
    • https://cdn.shopify.com/s/files/1/0435/3461/4688/files/sojexapeva.pdf
    • https://cdn.shopify.com/s/files/1/0432/8990/3259/files/mibeg.pdf
    • https://cdn.shopify.com/s/files/1/0433/2349/0457/files/tuviburor.pdf
    • https://cdn.shopify.com/s/files/1/0430/4296/3613/files/14135917334.pdf
    • https://cdn.shopify.com/s/files/1/0427/5906/1670/files/jobasubimo.pdf
    • https://cdn.shopify.com/s/files/1/0434/7707/4086/files/vaxudu.pdf
    • https://cdn.shopify.com/s/files/1/0437/4292/0869/files/1537539660.pdf
    • https://cdn.shopify.com/s/files/1/0435/3762/9348/files/61285430098.pdf
    • https://cdn.shopify.com/s/files/1/0431/6341/8784/files/fuwuledumusanagesik.pdf
    • https://cdn.shopify.com/s/files/1/0437/1765/6728/files/pogode.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_off0000720b.bin
7bab0b7e80a9b0a97369f96c5bc9da15905ce72b1412ece8413f4810782114ee
pdf-font-stream PDF embedded font (sfnt) at offset 0x720B 5464 bytes
font_01_sfnt_off0000848b.bin
85a149473e7f181e3b7bc11fdc77d6a0fec96aef53175c32e18cad6cbbdf13b3
pdf-font-stream PDF embedded font (sfnt) at offset 0x848B 9968 bytes