Malicious PDF — malware analysis report

Static analysis result for SHA-256 28dcb582c42d39bb…

MALICIOUS

PDF

48.6 KB Created: 2020-07-09 06:56:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-08-25
MD5: c3f74504bebe8df2713832b997165ea3 SHA-1: 0e01e52e560c65f0ae84388d1a3a7d06e955ce1f SHA-256: 28dcb582c42d39bbb81a1febaab8bd1df9305a7a44540c63f20588afe20c20de
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains a large number of embedded links, many of which point to domains commonly used in SEO link farms. One critical heuristic identified a link to a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains URLs that are also present in the heuristic findings, reinforcing the malicious link farm and redirector attack pattern.

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.cc/wb?keyword=vivado%20zynq%20tutorial%20pdf In PDF document text
    • http://files.colneyheathvillagehall.com/uploads/1/3/1/6/131606819/155b9f8f.pdfIn PDF document text
    • http://files.lrcboutique.com/uploads/1/3/2/3/132303378/tenegodu.pdfIn PDF document text
    • http://files.firststatebaptist.com/uploads/1/3/2/6/132681824/3383757.pdfIn PDF document text
    • http://files.ucvillagegarden.net/uploads/1/3/1/4/131414516/1076606.pdfIn PDF document text
    • http://files.myuplanddental.com/uploads/1/3/1/0/131071056/xepebezobapepukono.pdfIn PDF document text
    • http://files.legacyhorselogging.com/uploads/1/3/1/6/131636990/rakofidi-tuxujojaxeki.pdfIn PDF document text
    • http://files.aawholesaledallas.com/uploads/1/3/1/1/131163945/8f745b.pdfIn PDF document text
    • http://files.body-knowledge.com/uploads/1/3/2/6/132681824/2094315.pdfIn PDF document text
    • http://files.changingfutures.org.uk/uploads/1/3/1/6/131606087/mufegesitawiko-matuwomap-xivekun-vokozufeletefuz.pdfIn PDF document text
    • http://files.merrifieldseminar.com/uploads/1/3/2/7/132710655/7749287.pdfIn PDF document text
    • http://files.fromaboveyouthcenterandbakery.com/uploads/1/3/1/8/131871781/1727ab85.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://borexazirule.files.wordpress.com/2020/07/87093864620.pdfIn PDF document text
    • https://nogekidopof.files.wordpress.com/2020/06/61544968928.pdfIn PDF document text
    • https://jisabiwofif966812601.files.wordpress.com/2020/06/43135562853.pdfIn PDF document text
    • https://pewinutol.files.wordpress.com/2020/06/putajowokunafon.pdfIn PDF document text
    • https://xivatuzivo.files.wordpress.com/2020/07/24431667052.pdfIn PDF document text
    • https://pularazuwuva.files.wordpress.com/2020/07/wuwuro.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/13139855908.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/dojezurin.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/63537272249.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/zeranosorijajigafa.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/8007882555.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/9284441163.pdf?v=1594212706In PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/13879903487.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_off0000743e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x743E 4924 bytes
SHA-256: f4bcbaf1e2e56928c0ec1c7fd83ed667b59aba03aec9b10168f531a6d066a0f6
font_01_sfnt_off00008517.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8517 15440 bytes
SHA-256: 74a225f69745cacc25445d9adc98db02379d64ee93b3b06024edaacad61a7a39