Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b6da4eb38104034…

MALICIOUS

PDF

38.7 KB Created: 2020-08-04 14:45:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 10ac089c59e521753a10f8009ba97fb4 SHA-1: 5b3e4fd87ae543534905a2cfed8932c6504088f9 SHA-256: 7b6da4eb381040341ac84c18de8f7939709e615dc2ccef47ffe8c9a474eebcf2
152 Risk Score

Malware Insights

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

The PDF contains a mass external link farm, with a primary URL pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text that appears to be a lure for a 'psychological assessment sample pdf'. The ML classifier strongly indicated maliciousness. The primary malicious IOC is the redirector URL, which likely leads to further malicious content or phishing pages.

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=psychological+assessment+sample+pdf
    • http://files.lambethlarder.org/uploads/1/3/1/4/131438071/fovikison.pdf
    • http://files.missionbeachcentennial.org/uploads/1/3/0/7/130738720/2182158.pdf
    • http://files.profpaulgilbert.co.uk/uploads/1/3/2/7/132740533/7225939.pdf
    • http://files.highwaysnhoofbeats.com/uploads/1/3/1/3/131383541/05f54690a851747.pdf
    • https://cdn.shopify.com/s/files/1/0432/4940/2016/files/nikufojavola.pdf
    • https://cdn.shopify.com/s/files/1/0427/7446/2631/files/15119728330.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/tufajotojitumawudawemir.pdf
    • https://cdn.shopify.com/s/files/1/0428/2174/6847/files/71085392634.pdf
    • https://cdn.shopify.com/s/files/1/0434/3106/7813/files/8467765545.pdf
    • https://cdn.shopify.com/s/files/1/0431/4424/9499/files/zukusopar.pdf
    • https://cdn.shopify.com/s/files/1/0434/0147/8307/files/70897559295.pdf
    • https://cdn.shopify.com/s/files/1/0437/3879/2085/files/puxuxu.pdf
    • https://cdn.shopify.com/s/files/1/0433/9322/0758/files/42156628876.pdf
    • https://cdn.shopify.com/s/files/1/0431/5817/5908/files/sigopajixuxelupisede.pdf
    • https://cdn.shopify.com/s/files/1/0431/2875/0234/files/tvpad_server_down_2015.pdf
    • https://cdn.shopify.com/s/files/1/0427/4978/8327/files/10863185980.pdf
    • https://cdn.shopify.com/s/files/1/0431/5460/4198/files/44617907816.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_off000058f2.bin
53b1e35e50ff1b1630fd13cc9373edbc05dbc334bf3aa7da4ae89a4839a9f976
pdf-font-stream PDF embedded font (sfnt) at offset 0x58F2 5576 bytes
font_01_sfnt_off00006bd4.bin
23ffb1b5777120712cacfe01f9722c562538b3f4dd4d8edac8ba10da04c73dd2
pdf-font-stream PDF embedded font (sfnt) at offset 0x6BD4 10064 bytes