Malicious PDF — malware analysis report

Static analysis result for SHA-256 876119a9ebe4bc00…

MALICIOUS

PDF

73.0 KB Created: 2021-05-02 00:44:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: b8f920457852b1ea6759c5819b58ef88 SHA-1: 42d13572ba09789173a5b897e58791d07bf47edf SHA-256: 876119a9ebe4bc00f9abaa6e85c47b1b8c24f4a2d5685d3748eccccac50f78fb
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO spamming operation. The document body's text, 'What is the temperature and humidity outside right now', combined with the URL 'https://bologen.ru/strik?utm_term=what+is+the+temperature+and+humidity+outside+right+now', suggests a lure to a phishing or malicious site. ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://bologen.ru/strik?utm_term=what+is+the+temperature+and+humidity+outside+right+now PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4377400/normal_60445e4a96244.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369334/normal_606ba68397e22.pdfIn PDF document text
    • https://reponobokuwe.weebly.com/uploads/1/3/5/4/135401207/4767853.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406514/normal_601ed04155e66.pdfIn PDF document text
    • https://gizutiki.weebly.com/uploads/1/3/4/4/134478998/miwewevu.pdfIn PDF document text
    • https://fewefemuge.weebly.com/uploads/1/3/4/3/134372507/tuwabizajez.pdfIn PDF document text
    • http://nuverlites.online/universal_usb_audio_driver_mac2y31i.pdfIn PDF document text
    • http://mxbur.fun/how_to_sync_fitbit_charge_hr4o1dx.pdfIn PDF document text
    • https://mapaluloxusogor.weebly.com/uploads/1/3/0/7/130739646/51d9c86ea19ed.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485801/normal_605bc4578073e.pdfIn PDF document text
    • http://muldwych.com/suromavibewewafewjbwy4.pdfIn PDF document text
    • https://gefeteki.weebly.com/uploads/1/3/4/3/134310298/rebalo_nutigijixata_rigev.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381988/normal_604fa9124035b.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fuwutowamig.myartsonline.com/gettysburg_address_bliss_copy.pdfIn PDF document text
    • https://2386e270-bd20-42c1-b3e5-1ba7eaa1d68d.filesusr.com/ugd/b4f0c6_d05c57b1e3664361a1bee384b6cf7b16.pdf?index=trueIn PDF document text
    • https://ee6e56e8-c390-49d2-810b-d4defef8b9c1.filesusr.com/ugd/eda187_dbe0911fbd244b0e9b49180c4eae8d55.pdf?index=trueIn PDF document text
    • http://zugagib.atwebpages.com/maximum_bending_moment.pdfIn PDF document text
    • https://6a24fdd2-d4a5-4c4b-882b-0f3115751bcf.filesusr.com/ugd/04e6f9_1d4c44d7d93d44049a847db79cf50ec3.pdf?index=trueIn PDF document text
    • https://0ffdd24b-620b-4f4d-94ef-a39da1ca20bd.filesusr.com/ugd/853ce2_e46e2ee547e444e8a847e965fb4d5d11.pdf?index=trueIn PDF document text
    • https://70a023e4-b173-4b34-8ac5-854d526a16b0.filesusr.com/ugd/5aec30_70afbeb688e448dbbd60946cfdebac1d.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE015 5548 bytes
SHA-256: c9944e11b2e1145e23ce1351c2c5ff8c10ccee0c735850749680e8a382063848
font_01_sfnt_off0000f2e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E4 10400 bytes
SHA-256: 894d22ed565964f586f0c00672b0ac740195447009158773f5c2f106788d73ca