Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7b0d4a49cdfeb8c…

MALICIOUS

PDF

39.2 KB Created: 2020-08-14 22:33:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 249d4397cdfab855c3ecb7468f63cb1f SHA-1: 26832d8cf922d0b5cc79f6d344b1341ff7c44e44 SHA-256: a7b0d4a49cdfeb8c1a173194b06913103dc55034fc28237bb810a806e7d63dc8
154 Risk Score

Malware Insights

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

The PDF contains embedded links that redirect to malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though partially corrupted, contains text suggesting it is a lure for a study guide, which is then linked to a malicious URL. The ML_NYX_PDF_MALICIOUS heuristic further supports the malicious classification.

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 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.
  • 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/wb?keyword=official%20gre%20quantitative%20reasoning%20volume%202%20pdf
    • http://files.m28global.org/uploads/1/3/0/7/130739043/9cf615a96bf9e.pdf
    • http://files.sunfasteners.net/uploads/1/3/2/7/132712413/2809176.pdf
    • https://cdn.shopify.com/s/files/1/0432/5143/3627/files/30768054121.pdf
    • https://cdn.shopify.com/s/files/1/0430/3713/0914/files/mobojijuduwitepi.pdf
    • https://cdn.shopify.com/s/files/1/0430/0151/2095/files/lozefewej.pdf
    • https://cdn.shopify.com/s/files/1/0435/2675/0357/files/managerial_accounting_weygandt_6th_edition_solution_manual.pdf
    • https://cdn.shopify.com/s/files/1/0434/9027/9574/files/gcta_philippines.pdf
    • https://cdn.shopify.com/s/files/1/0436/2538/2051/files/best_android_spelling_test_app.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/73930450062.pdf
    • https://cdn.shopify.com/s/files/1/0428/2764/5084/files/58979004031.pdf
    • https://cdn.shopify.com/s/files/1/0438/2579/1133/files/impractical_jokers_season_4.pdf
    • https://cdn.shopify.com/s/files/1/0429/0471/5427/files/16241286857.pdf
    • https://cdn.shopify.com/s/files/1/0439/1885/2264/files/44908651950.pdf
    • https://cdn.shopify.com/s/files/1/0435/1819/7912/files/bodun.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005983.bin
3da478b34e79403664c1dd8d5d4b38c0460ca3cf4a105da7ea8b2dd8147f1443
pdf-font-stream PDF embedded font (sfnt) at offset 0x5983 5820 bytes
font_01_sfnt_off00006d41.bin
9a8d126080c80218f05115573c7ff75be58983081869e9340ccc7dbc8f168c6b
pdf-font-stream PDF embedded font (sfnt) at offset 0x6D41 10232 bytes