Malicious PDF — malware analysis report

Static analysis result for SHA-256 91f5a1b8fc1822fd…

MALICIOUS

PDF

46.0 KB Created: 2020-07-16 00:47:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-07
MD5: a86b98d3997706c2c00024674eb27f0c SHA-1: 7d294cce306c2ae78ad3a09a4e30ecb74aeab945 SHA-256: 91f5a1b8fc1822fdf523d2956c8bce1b296bd8737d6fa80b8cd680199db41b4a
194 Risk Score

Malware Insights

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

This PDF file contains multiple embedded links, with one specifically pointing to a known malicious redirector. The ML classifier also strongly flagged this file as malicious. The primary attack pattern involves luring the user to malicious websites through deceptive links, likely for further exploitation or credential harvesting.

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=quantifiers%20worksheet%20with%20answers%20pdf In PDF document text
    • http://files.rokforcefusion.com/uploads/1/3/0/8/130873914/vonajataw.pdfIn PDF document text
    • http://files.appliancerepairmacon.com/uploads/1/3/1/4/131483440/zufumava.pdfIn PDF document text
    • http://files.sbcopywriting.com/uploads/1/3/2/7/132740218/644292.pdfIn PDF document text
    • http://files.firstathens.org/uploads/1/3/2/7/132710687/9347935.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://mubupowe.files.wordpress.com/2020/06/rikuduwaxijuziluxalil.pdfIn PDF document text
    • https://xusurubisi.files.wordpress.com/2020/06/25740341961.pdfIn PDF document text
    • https://dazafokikup.files.wordpress.com/2020/07/93623173543.pdfIn PDF document text
    • https://rarimuvu282494435.files.wordpress.com/2020/06/timakizijutupogasomufo.pdfIn PDF document text
    • https://bivuwid.files.wordpress.com/2020/06/fezumarufa.pdfIn PDF document text
    • https://xisipitojeg.files.wordpress.com/2020/07/nuxefogipiwuxu.pdfIn PDF document text
    • https://zezumova.files.wordpress.com/2020/07/gevamo.pdfIn PDF document text
    • https://tefaluvutas.files.wordpress.com/2020/07/69221657283.pdfIn PDF document text
    • https://vewobarixi.files.wordpress.com/2020/07/xuvidapisedalozujexa.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/8946/1410/files/kigemoperemewugamosulo.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/3848/2332/files/likimogawez.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/7511/6964/files/14813981522.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/5466/0758/files/kipip.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/0195/3952/files/63452139836.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/40169505762.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/2891/4074/files/divakase.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/zixetirubopejama.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/suramagufumaxuragozud.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_off000077a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x77A6 5196 bytes
SHA-256: 31015a4c0412775622f8584ba4101c9febf06bf15ba033cce0022d3e708a72bf
font_01_sfnt_off0000895b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x895B 9684 bytes
SHA-256: 6cd78b885094a566a07adf12e90a94ba9bbfe20edd622d49161ede38d6e6dcfb