Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f7ab15fe531788f…

MALICIOUS

PDF

46.2 KB Created: 2020-08-25 13:51:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a65b8974a416819aef4342aca2b1dd42 SHA-1: 5f538d41d1898ae373dd65273d3ead177169f274 SHA-256: 0f7ab15fe531788f2ecebd80b9e827086e9f70280eb046fd1552655479006232
174 Risk Score

Malware Insights

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

The PDF contains a link to a redirector service, which is a common tactic for phishing and malware distribution. The document body, though heavily obfuscated, contains text related to 'free handwriting worksheets' and a URL that aligns with the heuristic findings. 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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.ru/pify?keyword=free+handwriting+worksheets+for+1st+grade
    • http://majidalo.dipconcaribbean.com/uploads/1/3/0/7/130739267/sejus.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/5580/0739/files/zesabarizutadupusodurod.pdf
    • https://cdn.shopify.com/s/files/1/0432/4042/3587/files/15425659544.pdf
    • https://cdn.shopify.com/s/files/1/0463/3388/6626/files/potica_aristteles_portugues.pdf
    • https://cdn.shopify.com/s/files/1/0432/2269/6096/files/30112486203.pdf
    • https://cdn.shopify.com/s/files/1/0432/9956/9829/files/dental_caries_book_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/rowogumidakedodovejizana.pdf
    • https://cdn.shopify.com/s/files/1/0429/1241/5907/files/vibimoz.pdf
    • https://cdn.shopify.com/s/files/1/0428/7502/7619/files/tefoteduporagiwimijobavep.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000776e.bin
18a60427f6198b78111b5265a76428229c2f678fbdb726321ccf6e430feff777
pdf-font-stream PDF embedded font (sfnt) at offset 0x776E 5300 bytes
font_01_sfnt_off0000898a.bin
10d551d3cbcd69a714baafc871d0d9c59ed757c4051ad731932ef4e2094ffd1c
pdf-font-stream PDF embedded font (sfnt) at offset 0x898A 9996 bytes