Malicious PDF — malware analysis report

Static analysis result for SHA-256 7fb476c005be7f31…

MALICIOUS

PDF

35.3 KB Created: 2020-10-07 22:40:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 242cbe867839e26b16774ecce13f8502 SHA-1: 8e9022d510b4cff4a40f25b2b4510cfee00e85f5 SHA-256: 7fb476c005be7f3175763a36e0544fc037866c20067ee72eef1a73382f2435f6
124 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by an ML classifier and contains embedded URLs pointing to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains a URL that appears to be a lure for educational materials, likely intended to trick users into clicking the malicious link. The presence of multiple links to disposable hosting further supports a malicious intent to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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 is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.me/pify?keyword=digraphs+worksheets+for+kindergarten+pdf
    • https://site-1039656.mozfiles.com/files/1039656/lelanowutab.pdf
    • https://site-1039948.mozfiles.com/files/1039948/60243433616.pdf
    • https://site-1036785.mozfiles.com/files/1036785/bapigeguwojopirumij.pdf
    • https://site-1036681.mozfiles.com/files/1036681/zimowusi.pdf
    • https://site-1040785.mozfiles.com/files/1040785/83226240309.pdf
    • https://site-1043455.mozfiles.com/files/1043455/pelinosiwadeju.pdf
    • https://site-1037266.mozfiles.com/files/1037266/76586352630.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0266/8252/3834/files/nijamexafezakawizabov.pdf
    • https://cdn.shopify.com/s/files/1/0483/6140/6617/files/interesting_npcs_multiple_followers.pdf
    • https://cdn.shopify.com/s/files/1/0493/1931/3569/files/reading_a_ruler_in_mm.pdf
    • https://cdn.shopify.com/s/files/1/0498/0342/7993/files/ear_acupuncture_points_for_weight_loss.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_off00004b5f.bin
c4a40616d455484fbff0cb0f439c20f103edce17beeb223d389d711d3963cac7
pdf-font-stream PDF embedded font (sfnt) at offset 0x4B5F 5428 bytes
font_01_sfnt_off00005de9.bin
0a3c6155b7a84726684a30a6a8bb03d8f7888908e4d16042d300f3bdcfd59e12
pdf-font-stream PDF embedded font (sfnt) at offset 0x5DE9 10036 bytes