Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3fbdc58a2d2ebb4…

MALICIOUS

PDF

83.6 KB Created: 2021-10-05 18:45:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 516729ab3ab8b6b560995e08d05a2d90 SHA-1: 19d52175bc72dba887d10bc224118005ce29d660 SHA-256: a3fbdc58a2d2ebb4b763d50a9e93b50586bac8592aacfc51a80888b132db26f1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm hosted on disposable domains, likely to distribute malicious content or phish for credentials. The embedded URLs point to suspicious domains, further supporting the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 5

  • 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://laborke.ru/uplcv?utm_term=will+have+had+tense PDF link annotation
    • http://taispacedesign.com/upload/files/27347474138.pdfIn PDF document text
    • https://palet-school.com/files/files/55814431435.pdfIn PDF document text
    • https://dammesliepas.lv/ckfinder/userfiles/files/tepepuxixokerufava.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/nudazemarenisekivekiw.pdfIn PDF document text
    • http://hastensandbreakfast.nl/userfiles/file/xejadenozakokopigud.pdfIn PDF document text
    • http://opuspointpartners.com/ckfinder/userfiles/files/ruxiximedepatagew.pdfIn PDF document text
    • http://fskyok.com/uploadfile/files/14620022938.pdfIn PDF document text
    • https://kanat.com/upload/ckfinder/files/85000971920.pdfIn PDF document text
    • https://aquarell.ro/userfiles/file/29331849485.pdfIn PDF document text
    • https://facades-et-traditions.com/actualites/file/48180158401.pdfIn PDF document text
    • https://xn--80apefbdm9ah5g.xn--p1ai/userfiles/levosoranafabeji.pdfIn PDF document text
    • https://rjpexport.com/files/sajaledasotapovefa.pdfIn PDF document text
    • http://avandcie-automation.fr/ckfinder/userfiles/files/51866129105.pdfIn PDF document text
    • http://studioprogettoarchitettura.eu/userfiles/files/47264812349.pdfIn PDF document text
    • http://fred-robin.com/ckfinder/userfiles/files/mavoraralugisinirigidaru.pdfIn PDF document text
    • http://ktcz.eu/files/files/litujar.pdfIn PDF document text
    • https://zifu-tech.com/app/webroot/userfiles/files/vunibepalar.pdfIn PDF document text
    • http://www.polni.si/Images/files/lexazopi.pdfIn PDF document text
    • http://hotelbasantresidency.com/uploads/zekewitataba.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613afed6a3a7e---ximef.pdfIn PDF document text
    • http://infoegrafica.com/userfiles/files/33514992283.pdfIn PDF document text
    • http://flapboxes.com/userfiles/files/5570975036.pdfIn PDF document text
    • https://www.db-ynox.fr/ckfinder/userfiles/files/nekoziwalelebefeponogorif.pdfIn PDF document text
    • https://atamergranit.com/userfiles/file/zuparazitaji.pdfIn PDF document text
    • https://speakingparrot.com/upload/ckfinder/files/99266984007.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615b8728eda36---tivokotefiwijipurerop.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://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_off0000e512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE512 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD29 10184 bytes
SHA-256: 1e619f2259cfe23f8269e274ce716482a759215bfc47ebee1fa883e4ed54f36e
font_02_sfnt_off000113dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113DD 17524 bytes
SHA-256: 4247b763f172771d20908be3879170fd69fd2b4307def0f6322e6bfdc3515bd0