Malicious PDF — malware analysis report

Static analysis result for SHA-256 4603c9e0ac89ab0b…

MALICIOUS

PDF

84.5 KB Created: 2021-05-22 18:29:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: c4bd49b9d1c0bb11e8ca02a8d745452b SHA-1: 2bc6cdf29743ad8a8ac07885706aa8ac456a6a42 SHA-256: 4603c9e0ac89ab0ba146d18db006a1e8ab433927ff0f2bff3297453f89f8916c
196 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which are part of an SEO link farm, indicating a malicious intent to drive traffic to specific sites. The heuristic 'PDF_SEO_UTM_REDIRECTOR_LINK' specifically flags an image lure linking to an SEO redirector at 'https://gimoguvi.ru/strik?utm_term=all+the+months+and+their+zodiac+signs', suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection further support the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

Heuristics 6

  • 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 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://gimoguvi.ru/strik?utm_term=all+the+months+and+their+zodiac+signs PDF link annotation
    • https://sokijolixorinus.weebly.com/uploads/1/3/1/1/131163896/fca2e757ae04.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457281/normal_5fca43472533e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416796/normal_600a41045755c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402718/normal_601465c805d96.pdfIn PDF document text
    • https://pakipuxis.weebly.com/uploads/1/3/5/3/135347710/fakotadugebeke.pdfIn PDF document text
    • https://giwuvapelefawi.weebly.com/uploads/1/3/4/8/134869604/gorajolaxu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4401716/normal_60698c7ea4664.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366341/normal_5fd2ad40edbcd.pdfIn PDF document text
    • https://jizufuvarax.weebly.com/uploads/1/3/1/1/131164460/ab9c6446c38f94f.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/wizuluworafid/archaeologist_bard_guide_pathfinder.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1280343d-474b-4345-9a42-f4b584d61ca6/bojoluda.pdfIn PDF document text
    • https://s3.amazonaws.com/kokesatodixon/gestational_trophoblastic_disease_guidelines_acog.pdfIn PDF document text
    • https://s3.amazonaws.com/batoragubukepo/bejowumixoderajeraf.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c597b2ad-e2bf-4be6-8de4-38f439aff38f/3_billy_goats_gruff_colouring_pictures.pdfIn PDF document text
    • https://s3.amazonaws.com/gezizefefififa/kobavuwafizewuxog.pdfIn PDF document text
    • https://s3.amazonaws.com/bevarolimesale/zowotabumatuderafur.pdfIn PDF document text
    • https://s3.amazonaws.com/simujix/47844939075.pdfIn PDF document text
    • https://s3.amazonaws.com/wivunonovef/airline_safety_management_system_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/risisipajole/indian_army_whatsapp_status_video_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/978394cd-cf79-4948-adfa-a18198c4fb74/how_to_use_gopro_hero_4_as_webcam_without_hdmi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e0d20952-cec9-4782-8725-41de6341073e/39217733724.pdfIn PDF document text
    • https://s3.amazonaws.com/wekibik/19731336471.pdfIn PDF document text
    • https://s3.amazonaws.com/tumuzu/kexuzovukuxopo.pdfIn PDF document text
    • https://s3.amazonaws.com/sizabo/puzezes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e94dab07-dab6-4714-9674-183a3215f64d/64693052607.pdfIn PDF document text
    • https://s3.amazonaws.com/banula/nudap.pdfIn PDF document text
    • https://s3.amazonaws.com/tuxenipup/goku_vs_android_19_dublado_completo.pdfIn 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f559.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF559 5392 bytes
SHA-256: a5d5b5c4ba29f555be51c8502e4de8838560ce6f1c573695d657843f81df3304
font_01_sfnt_off00010784.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10784 11060 bytes
SHA-256: b9c16db271b9082379ddc1c50a709b59b13ab6b31492f40d0b81ab6d2ade33b4
font_02_sfnt_off00012c65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C65 16296 bytes
SHA-256: 1eb2d602a8f0fbd29cf35e28249ef192f748b5a163674ba4d9c287d47c1a48c9