Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbc9e333f828428a…

MALICIOUS

PDF

46.0 KB Created: 2020-08-20 22:58:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c4ae48adaa2111a77ff6aa0de57c47ff SHA-1: e1438e3fd9db9a3165227ce7123c9a00aa308b93 SHA-256: dbc9e333f828428a4b002957b28bffc68e94c2cfd336d975ce73f9fc4c6915bf
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic firing indicating it redirects to known malicious infrastructure. The document body, though heavily obfuscated, contains a URL that matches the one identified by the heuristic. The ML classifier also strongly flagged this PDF as malicious. The primary attack vector appears to be a lure to click on a malicious link.

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/pify?keyword=checklist+format+for+construction
    • http://fepuwivon.ayusewingproject.org/uploads/1/3/1/4/131454526/9890535.pdf
    • http://vuzoja.katiecarrington.com/uploads/1/3/0/8/130814328/a5aa8b4f16a1.pdf
    • http://files.littlelyricist.com/uploads/1/3/1/0/131069781/7f026eee7dda.pdf
    • http://files.pettigrew316.com/uploads/1/3/2/6/132695278/filagiwedav.pdf
    • http://dadekus.sarahtiltonart.com/uploads/1/3/0/9/130969503/659167.pdf
    • https://cdn.shopify.com/s/files/1/0432/7260/1756/files/fojejox.pdf
    • https://cdn.shopify.com/s/files/1/0427/6636/8935/files/lorubi.pdf
    • https://cdn.shopify.com/s/files/1/0432/8354/6267/files/ketogenic_food_plan.pdf
    • https://cdn.shopify.com/s/files/1/0428/1391/5303/files/35154301860.pdf
    • https://cdn.shopify.com/s/files/1/0430/8946/1410/files/34796896306.pdf
    • https://cdn.shopify.com/s/files/1/0428/2803/8310/files/44999271561.pdf
    • https://cdn.shopify.com/s/files/1/0430/4951/7205/files/kejusawiwemudunesi.pdf
    • https://cdn.shopify.com/s/files/1/0431/8897/7813/files/autobiography_of_a_river_ganga_in_2500_words.pdf
    • https://cdn.shopify.com/s/files/1/0428/9078/9020/files/15678330247.pdf
    • https://cdn.shopify.com/s/files/1/0431/3051/9716/files/89486302034.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_off000077a8.bin
cf35fc5321dcd52f5916d9036c360711c6ea8d9d76760aee573745c819da55eb
pdf-font-stream PDF embedded font (sfnt) at offset 0x77A8 5092 bytes
font_01_sfnt_off000088c7.bin
f5e7eee8a4d54d31caa7dd20e991d76bf4a161d6f2803a76a0f7ce5a66c722d9
pdf-font-stream PDF embedded font (sfnt) at offset 0x88C7 9980 bytes