Malicious PDF — malware analysis report

Static analysis result for SHA-256 737ef015eb3f077b…

MALICIOUS

PDF

85.9 KB Created: 2021-05-06 02:17:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-20
MD5: 00f35f27e3b0782e94360b33a7292e8d SHA-1: df956ba3e04836b8f2a946d8ae9202e1629f4d73 SHA-256: 737ef015eb3f077bb7a40226263b7cf0d9ba85760784396a57a0338229e46cd9
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting services like weebly.com and sqhk.co. Heuristics indicate this is a link farm designed to obscure the true destination, and ClamAV detected it as a phishing trojan. The embedded document body is heavily obfuscated and appears to be junk data, suggesting the primary purpose is to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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.
  • 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://fawurefo.weebly.com/uploads/1/3/4/4/134441885/322d67b300.pdf In PDF document text
    • https://lolozodosut.weebly.com/uploads/1/3/1/6/131606575/3429289.pdfIn PDF document text
    • https://cdn.sqhk.co/wifopuzuxiba/ihrGfhh/incoming_goblins_attack_tower_defense_strategy_guide.pdfIn PDF document text
    • https://wewiruvikaju.weebly.com/uploads/1/3/0/7/130775929/gudev.pdfIn PDF document text
    • https://cdn.sqhk.co/seponidozit/egcKhcY/40502063479.pdfIn PDF document text
    • https://cdn.sqhk.co/vobilurerire/ighc2hi/cha_cha_cha_dance_video_free.pdfIn PDF document text
    • https://bitabado.weebly.com/uploads/1/3/1/4/131436956/7787625.pdfIn PDF document text
    • https://vejarava.weebly.com/uploads/1/3/1/0/131070596/dulufuf.pdfIn PDF document text
    • https://pujuwofox.weebly.com/uploads/1/3/4/8/134882524/nikodujawewid.pdfIn PDF document text
    • https://cdn.sqhk.co/rabataxuvax/zQvQygf/the_survivor_movie_cast.pdfIn PDF document text
    • https://safamitiwifiro.weebly.com/uploads/1/3/0/7/130739579/xusisigada_nibizusuzebude.pdfIn PDF document text
    • https://dadurafiwazozu.weebly.com/uploads/1/3/4/7/134768329/rotelosaku_garukadak_litujekur.pdfIn PDF document text
    • https://sebinegovana.weebly.com/uploads/1/3/4/0/134095930/lurufunanono-dilisidofam-ziwabuvixa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://feedproxy.google.com/~r/wb/ENAH/~3/0IJhScypsXo/wb?keyword=bb%20flat%20tuba%20finger%20chart%203%20valvePDF link annotation
    • https://s3.amazonaws.com/xoxaneral/6698319161.pdfIn PDF document text
    • https://973697ad-ffa4-4f9d-85cd-0c9d1ea039ee.filesusr.com/ugd/5f5755_71e006a032b4421cae07217c9f8f427b.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xirixepo/dafunozu.pdfIn PDF document text
    • https://11484d69-1612-41b9-9199-165df1f08223.filesusr.com/ugd/e2f197_513ffafb89024b6d87f24cc035c283e5.pdf?index=trueIn PDF document text
    • https://b5526579-b22d-45a0-8251-9885a72cf3eb.filesusr.com/ugd/0cd019_d0c208cf732948da832a7020992cd18c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zoromexemuzid/grohe_kitchen_tap_fitting_instructions.pdfIn PDF document text
    • https://a540aa65-2eb1-4ac3-86d0-bf6a54daac96.filesusr.com/ugd/2d797c_37ede20cdba0472887d12e13149e4298.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/veledabejufi/how_to_search_pictures_on_google_android.pdfIn PDF document text
    • http://gutekuretejapoj.onlinewebshop.net/nizeg.pdfIn PDF document text
    • http://nowageg.onlinewebshop.net/30640354721.pdfIn PDF document text
    • https://28a90398-13b1-4b58-b54c-ed045a6bddf2.filesusr.com/ugd/7e9e1f_4fb42c33dd49400d9a5bd0e435cda32f.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
    • 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_off0000f9e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E7 5380 bytes
SHA-256: 10a783b672a325f63fcaa7b82fc4b2269ae01577730b2051139659194c4d82ed
font_01_sfnt_off00010c44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C44 11948 bytes
SHA-256: 57106eb0f8a43dfa4fc6b0ea3f1799be0a4e0ba7bf8d5a60ef507617b1ed74af
font_02_sfnt_off00013514.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13514 16120 bytes
SHA-256: fb7b45e24c28c4473d0ca1c6410c593992d9a809009f9c41b5ae32c9142507dd