Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f8953f16d76ca4b…

MALICIOUS

PDF

44.6 KB Created: 2020-08-13 18:58:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-09
MD5: 9d31eeda4bcbc4d6d305a9f96a95fa1d SHA-1: 5a9db73791b2e4c42d2bceaaffdd7782a4f7c6ad SHA-256: 5f8953f16d76ca4b09ac7d5a739d89a4b263ab0f8258a4404385ab2f64fc2c1a
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link that redirects to malicious infrastructure, disguised as a scholarship motivation letter. This is further supported by heuristics indicating a malicious redirector and a PDF link farm, suggesting a phishing or scam attempt. 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.
  • 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=sample%20motivation%20letter%20for%20scholarship%20pdf In PDF document text
    • http://files.coaster-notes.com/uploads/1/3/1/1/131164048/8788387.pdfIn PDF document text
    • http://tedezobel.avianaonline.com/uploads/1/3/0/8/130873995/naloriveko-jigazulifox-xotufedud-gurodevilo.pdfIn PDF document text
    • http://sedodevu.firstnewark.com/uploads/1/3/1/6/131606027/bea0fd.pdfIn PDF document text
    • http://potolojuf.goodindeedmusic.co.uk/uploads/1/3/2/8/132814930/631680.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://cdn.shopify.com/s/files/1/0430/1458/6517/files/lexopabevaroxunisevepon.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/2841/4618/files/86869060027.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0437/7228/0981/files/liwatajevebowelijemozo.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0435/4359/3109/files/niredulopufijukenove.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/2206/5557/files/60906276783.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/5386/6408/files/xuzugatidojol.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/9676/8661/files/gowedanupiz.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/6422/2101/files/pewidogenunenov.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/8362/8697/files/zipobonusisejiba.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/4218/6150/files/nezowo.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/5789/7882/files/70261856975.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005ff6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5FF6 5344 bytes
SHA-256: 4253e02af09c4035fd83406571eddc9f17f5bb37102e3ed8368ec80a1db1fdfb
font_01_sfnt_off000071ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x71EE 10420 bytes
SHA-256: 6f99fd42b56868681e8d3d2c0a49d382bf7ac8c94a338067523e25a047913da5
font_02_sfnt_off0000957f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x957F 4324 bytes
SHA-256: 8405bb6ca9a6fb718a2e910e1cdde4d74ac2122cab0061dc5f772322db9c7ccd