Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbb4605487391a48…

MALICIOUS

PDF

81.9 KB Created: 2021-09-19 05:16:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e898b1c81da736dca7248c8a039520d9 SHA-1: 56ceb04f6bc087d3d93b7809ff6c236d1611477e SHA-256: fbb4605487391a48e017283732e7b87eaa1fc21611e6c932b763b4d0ef87fadb
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and link farms pointing to various websites, many of which are hosted on disposable domains or compromised CMS instances. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and URI patterns are consistent with techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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.
  • 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://catamma.ru/uplcv?utm_term=download+apps+removed+from+play+store PDF link annotation
    • http://vetranhtuong.info/luutru/files/46934957744.pdfIn PDF document text
    • http://allamericannursing.com/userfiles/file/dugetozovuxu.pdfIn PDF document text
    • https://krygina40.ru/UserFiles/File/31708872888.pdfIn PDF document text
    • http://pkynfe.net/userfiles/file/didabisakusabino.pdfIn PDF document text
    • https://mekongtransport.com/upload/userfiles/files/zigatadobozavumo.pdfIn PDF document text
    • https://wmu24.ru/media/file/7745358157.pdfIn PDF document text
    • http://bobas24.pl/Upload/file/92402717895.pdfIn PDF document text
    • https://www.educationsexuelle-ecole.ch/ck/ckfinder/userfiles/files/90058857871.pdfIn PDF document text
    • https://foodsafebox.com/ckfinder/userfiles/files/12582936544.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/6119feefedb395d6d733c420fb1d843c/6270657430.pdfIn PDF document text
    • https://inprovitecuador.com/ckfinder/userfiles/files/87119896722.pdfIn PDF document text
    • http://140.121.161.111/ckfinder/userfiles/files/linativonugajaxex.pdfPDF link annotation
    • http://schokozentrale.de/idata/13678062114.pdfIn PDF document text
    • http://csc-0898.com/userfiles/file/20210902164727_1h98vs.pdfIn PDF document text
    • https://mexico-airport-transfers.com/ckfinder/userfiles/files/19400744072.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f872e2eee7---gimunibutadu.pdfIn PDF document text
    • http://gizmakina.com/depo/sayfaresim/file/75069112834.pdfIn PDF document text
    • http://www.mediagrand.hu/data/editorfile/jefavupugidemosi.pdfIn PDF document text
    • http://xz-brand.com/ckfinder/userfiles/files/66779607063.pdfIn PDF document text
    • https://namkhoasaigon.vn/web/images/files/33869239916.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161410e9ca6536---jotepivuf.pdfIn PDF document text
    • http://varosom.hu/userfiles/files/vamunixofu.pdfIn PDF document text
    • https://mediaget.com/userfiles/files/gubomijexuxotasan.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_off0000daf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f308.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF308 17352 bytes
SHA-256: 274a0863d527bc111e0773567d464f607dd2c83a125a81187febbb73125f9b28
font_02_sfnt_off0001205c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1205C 10836 bytes
SHA-256: cbbb5d405221daf6b883e24aa7af5d5ff6e151ea82eef1809bfe199cce4dd04b