Malicious PDF — malware analysis report

Static analysis result for SHA-256 19bed3c46ac7e558…

MALICIOUS

PDF

99.4 KB Created: 2021-09-13 00:52:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b0399221502a89b224d0b74b2776b0d2 SHA-1: 8f5710d663dd48a90c04f9fc1fb8ca79050c6a1a SHA-256: 19bed3c46ac7e55807f4e68347d98cd43ae86e760e6125d9a54f52883dd0ad39
184 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating malicious intent, including a ML classifier flagging it as malicious and ClamAV detecting it as Pdf.Phishing.Trojan. The presence of a download button lure and a callback phishing pretext suggests a social engineering attempt to trick the user. The document also contains numerous embedded URLs, many of which point to potentially compromised or disposable hosting, further supporting a malicious distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://alemotta.com/resources/original/file/94622375363.pdf In PDF document text
    • https://theloneranger.tv/clients/loneranger/ckfinder/userfiles/files/2202341677.pdfIn PDF document text
    • https://topupdana.com/contents/files/ribotixox.pdfIn PDF document text
    • https://wyslijpaczki.pl/app/webroot/files/userfiles/file/noxinanulukoj.pdfIn PDF document text
    • http://bassbasement.org/userfiles/file/52007652096.pdfIn PDF document text
    • https://projektovanje.info/userfiles/file/tetixapipe.pdfIn PDF document text
    • https://eastmanllc.net/ckfinder/userfiles/files/luxika.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/cbe35ff7d23e8cdad7b82e12aa54799e/bivilon.pdfIn PDF document text
    • http://abwpetersburg.com/uploads/files/fivojugawigipem.pdfIn PDF document text
    • http://builderall.info/userfiles/file/10315014039.pdfIn PDF document text
    • http://aktifbant.com/resimler/files/11011910295.pdfIn PDF document text
    • http://packamate.com/userfiles/40396194624.pdfIn PDF document text
    • http://niengrangchuyensau.com/upload/contentFile/file/76286609479.pdfIn PDF document text
    • https://denizlihorozu.com/resimler/files/jemogawusunuruxarekekira.pdfIn PDF document text
    • https://5udua.com/contents/files/64743778595.pdfIn PDF document text
    • http://architettomontanino.eu/userfiles/files/19262424089.pdfIn PDF document text
    • https://kalendarz.probik.pl/fckeditor/userfiles/file/78066395366.pdfIn PDF document text
    • http://massarentearchitettura.com/userfiles/files/28634121621.pdfIn PDF document text
    • https://marblobaths.com/app/webroot/img/files/64929424466.pdfIn PDF document text
    • http://sissonne.hu/editor_up/fanuvomezurebubuk.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3872a4885---48214617281.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f01d2dfde4---64298290957.pdfIn PDF document text
    • http://gewoongroen.eu/app/webroot/files/userfiles/files/bukatufufolo.pdfIn PDF document text
    • http://15441707.com/data/board/file/20210907173422.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=sending+cv+by+email+what+to+writePDF link annotation
    • 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_off00011ccf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CCF 18972 bytes
SHA-256: 3b4e7c8938a751d22dfe40596ecd30cd8ba306a8268587e0117f8ab075761bd6
font_01_sfnt_off00014e04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E04 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001661b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1661B 11132 bytes
SHA-256: 770fe9aecda3aa107184568c200cd46bdad3b24fe5367e0a427012aedcad04af