Malicious PDF — malware analysis report

Static analysis result for SHA-256 b13314657cf6f4f5…

MALICIOUS

PDF

78.8 KB Created: 2021-04-03 16:23:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8ca47b3b5486dfee8c9657d1fe39a614 SHA-1: 76f9fe657946dae9bee517a60c58deaf03e45113 SHA-256: b13314657cf6f4f5d151f9daa127b8487dff77dcea49bd9d2b6e9eb2e616e1b5
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many pointing to disposable hosting services like Weebly, indicating a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution through these links. No scripts were extracted, and the document body is heavily obfuscated, but the heuristic firings clearly point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://leonvi.ru/award?keyword=abraham+lincoln+books+pdf+download
    • https://bozixezexa.weebly.com/uploads/1/3/4/8/134861503/wanuliw.pdf
    • https://kuvikupomudu.weebly.com/uploads/1/3/4/4/134457818/matikisuvaxinad-simubizojusipi-rofutuni.pdf
    • https://nesefutuderixu.weebly.com/uploads/1/3/2/7/132740375/14a43a.pdf
    • https://wevejabunom.weebly.com/uploads/1/3/1/4/131406075/rilumapukariwek.pdf
    • https://cdn-cms.f-static.net/uploads/4475375/normal_5fe720e7b1b44.pdf
    • https://cdn.sqhk.co/tororukiwuri/hf7iax4/zogevijutiderivazofe.pdf
    • https://cdn-cms.f-static.net/uploads/4383695/normal_604de7098445e.pdf
    • https://turamuko.weebly.com/uploads/1/3/4/4/134458704/3728cf4e616affe.pdf
    • https://cdn.sqhk.co/xubipoxeguza/figzgjW/wukizabirefizowaji.pdf
    • https://static.s123-cdn-static.com/uploads/4421764/normal_5ff712a118186.pdf
    • https://cdn-cms.f-static.net/uploads/4459175/normal_600d52445dd29.pdf
    • https://xugubevowasisof.weebly.com/uploads/1/3/4/8/134885616/zefovagiviravike.pdf
    • https://vidufatow.weebly.com/uploads/1/3/1/4/131438098/1496666.pdf
    • https://jefupijoban.weebly.com/uploads/1/3/1/4/131437873/7fb73851a284.pdf
    • https://cdn.sqhk.co/tudenireso/higeNje/9073339263.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/jevedijadiki/insufisiensi_plasenta_adalah.pdf
    • https://uploads.strikinglycdn.com/files/7366e301-8245-41e9-a340-6dca7712e6ab/how_to_use_mxr_bass_compressor.pdf
    • https://uploads.strikinglycdn.com/files/8de21a80-f2c5-4c4d-81ca-a3e3360a8a8a/adobe_premiere_pro_free_download_full_version_for_pc_2020_crack_getintopc.pdf
    • https://s3.amazonaws.com/zupenafud/54149079535.pdf
    • https://uploads.strikinglycdn.com/files/fc50cd8e-d251-472b-ae05-fc34d016b36a/52659067835.pdf
    • https://s3.amazonaws.com/daraniwekamidir/15425253237.pdf
    • https://s3.amazonaws.com/suxugipipolazog/derixewi.pdf
    • https://uploads.strikinglycdn.com/files/19093451-7df5-4106-83a9-3882e443cee8/25841498112.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8bb.bin
6065c2dbd0e899e97c54212515db3a09c06942e52924d4ac593df3b1a73f3ea2
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8BB 5268 bytes
font_01_sfnt_off0000fa6b.bin
869adac359b9a3dffeef62e7d5920a057c86312570e2814a92be141e6225d464
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA6B 10784 bytes
font_02_sfnt_off00011f63.bin
9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F63 4324 bytes