Malicious PDF — malware analysis report

Static analysis result for SHA-256 639544ee27d3922d…

MALICIOUS

PDF

47.3 KB Created: 2020-11-03 19:09:48 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 8983e945c74138599ed38d3c773b756e SHA-1: e47c38bc31ab16fe00e919de092ac4319aaa506f SHA-256: 639544ee27d3922d28edccfc69833e746590b32fbbbc23b93900ad020003bb9e
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded links that point to a redirector infrastructure, identified by the 'PDF_MALICIOUS_REDIRECTOR_LINK' and 'PDF_SEO_UTM_REDIRECTOR_LINK' heuristics. The document body, though heavily obfuscated, contains references to URLs that are likely part of a phishing or malware distribution chain. The ML classifier also strongly indicated maliciousness.

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.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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.link/123?keyword=fha+condo+questionnaire+pdf In PDF document text
    • https://dojudiwoju.weebly.com/uploads/1/3/1/4/131406456/pajofuwigitidofo.pdfIn PDF document text
    • https://waxovidimised.weebly.com/uploads/1/3/4/4/134446407/xumebe_vigoxanijebusuz_zukekafa.pdfIn PDF document text
    • https://pekedilude.weebly.com/uploads/1/3/4/3/134324883/e4854d10f20.pdfIn PDF document text
    • https://kirimanadawa.weebly.com/uploads/1/3/4/3/134383910/6934788.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/viboxikuz/82319363094.pdfIn PDF document text
    • https://s3.amazonaws.com/fumiposamisur/tie_dye_bedding_diy.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/795d0904-9329-45aa-b68d-168954b4a53a/rebubuvitufefo.pdfIn PDF document text
    • https://s3.amazonaws.com/mudurixo/rafarikekajig.pdfIn PDF document text
    • https://s3.amazonaws.com/kavitokolezub/tekemipi.pdfIn PDF document text
    • https://s3.amazonaws.com/napisakaluja/chocolate_dachshund_puppy.pdfIn PDF document text
    • https://s3.amazonaws.com/damerirazib/kosatasazuzamorogebine.pdfIn PDF document text
    • https://s3.amazonaws.com/xumakomowi/wodomesavosebudek.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d67729af-2fc7-4e52-a732-87c043275b30/kenmore_heavy_duty_70_series_manual.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_off000079ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x79AB 5292 bytes
SHA-256: f1f13c1a3a30190dab0e2229979f6559c6f86ca7bd2e515c82d6a38f5d4b452f
font_01_sfnt_off00008ba5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8BA5 10940 bytes
SHA-256: 2324f9febc0c33730731b9db858131858bc992c4011b0b1445c3bb1c2672495e