Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b733138b840e7e4…

MALICIOUS

PDF

38.4 KB Created: 2020-07-08 23:11:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-08-25
MD5: 6864c60e3cb7e4eb472ad62c88a13bc4 SHA-1: 541cd7cfecb637ed88281b06cd9fd86fea4564c9 SHA-256: 8b733138b840e7e40fa4ec1e5bc4fb0014bf83dd93580523cfe942af3c8dadee
194 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, identified as a link farm. One critical heuristic indicates a redirector link to a known malicious domain, and another points to a large number of external PDF links, suggesting SEO poisoning or a similar lure. The document body contains obfuscated text and numerous URLs, reinforcing the malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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/wb?keyword=nmc%20code%202015%20pdf In PDF document text
    • http://files.rickrebelsrock.com/uploads/1/3/2/6/132695839/8171851.pdfIn PDF document text
    • http://files.delbertsonrealty.com/uploads/1/3/0/7/130776370/pitiw_zujutumokofu.pdfIn PDF document text
    • http://files.philprobstcyclist.com/uploads/1/3/0/9/130969404/nudaxox.pdfIn PDF document text
    • http://files.mylunarsign.com/uploads/1/3/1/8/131857482/6fcae3.pdfIn PDF document text
    • http://files.parksideict.com/uploads/1/3/2/8/132815172/pulekutozoper.pdfIn PDF document text
    • http://files.katascuba.com/uploads/1/3/1/4/131483253/5349126.pdfIn PDF document text
    • http://files.raphastar.com/uploads/1/3/1/6/131606720/momuramegu-zafapevunovudu.pdfIn PDF document text
    • http://files.rosesrntred.com/uploads/1/3/1/1/131164351/bobokadipuz_lebopogexugufor.pdfIn PDF document text
    • http://files.commentingtogether.com/uploads/1/3/1/8/131871778/duzijonuv.pdfIn PDF document text
    • http://files.westphaliarowhoa.com/uploads/1/3/1/6/131606762/3514558.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://jejukogizuf.files.wordpress.com/2020/07/78627594448.pdfIn PDF document text
    • https://gorowedezer.files.wordpress.com/2020/06/89356626276.pdfIn PDF document text
    • https://gimanuzil.files.wordpress.com/2020/06/57280460673.pdfIn PDF document text
    • https://zavigezanu.files.wordpress.com/2020/06/25827532790.pdfIn PDF document text
    • https://sowirule.files.wordpress.com/2020/07/deroxenibugolawoxiruvusi.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/gefoviliruvowej.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/sazofafusogowo.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/vasopamomakazemujavinis.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/gegexovikorojirokelaxedu.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/12729031526.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/53940500656.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/81159011373.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005946.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5946 4760 bytes
SHA-256: 0247b6cf9141942ccd5accab5b19478fc12d49363a3be739cfb74514d73ef641
font_01_sfnt_off0000697d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x697D 10288 bytes
SHA-256: d5154acd7f7c7c68f62d0c0f41c909045597fd06926b92b10a47de088d6e0798